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class="toctree-l3"><a class="reference internal" href="../tutorial/perform-findAndModify-linearizable-reads.html">Linearizable Reads via <code class="docutils literal"><span class="pre">findAndModify</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../core/query-plans.html">Query Plans</a></li><li class="toctree-l3"><a class="reference internal" href="../core/query-optimization.html">Query Optimization</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/evaluate-operation-performance.html">Evaluate Performance of Current Operations</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/optimize-query-performance-with-indexes-and-projections.html">Optimize Query Performance</a></li><li class="toctree-l4"><a class="reference internal" href="../core/write-performance.html">Write Operation Performance</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/explain-results.html">Explain Results</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/analyze-query-plan.html">Analyze Query Performance</a></li><li class="toctree-l3"><a class="reference internal" href="../core/tailable-cursors.html">Tailable Cursors</a></li></ul></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../aggregation.html">Aggregation</a><ul><li class="toctree-l2"><a class="reference internal" href="../core/aggregation-pipeline.html">Aggregation Pipeline</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/aggregation-pipeline-optimization.html">Aggregation Pipeline Optimization</a></li><li class="toctree-l3"><a class="reference internal" href="../core/aggregation-pipeline-limits.html">Aggregation Pipeline Limits</a></li><li class="toctree-l3"><a class="reference internal" href="../core/aggregation-pipeline-sharded-collections.html">Aggregation Pipeline and Sharded Collections</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/aggregation-zip-code-data-set.html">Example with ZIP Code Data</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/aggregation-with-user-preference-data.html">Example with User Preference Data</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/map-reduce.html">Map-Reduce</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/map-reduce-sharded-collections.html">Map-Reduce and Sharded Collections</a></li><li class="toctree-l3"><a class="reference internal" href="../core/map-reduce-concurrency.html">Map-Reduce Concurrency</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/map-reduce-examples.html">Map-Reduce Examples</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/perform-incremental-map-reduce.html">Perform Incremental Map-Reduce</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/troubleshoot-map-function.html">Troubleshoot the Map Function</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/troubleshoot-reduce-function.html">Troubleshoot the Reduce Function</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/aggregation.html">Aggregation Reference</a><ul><li class="toctree-l3"><a class="reference internal" href="../meta/aggregation-quick-reference.html">Aggregation Pipeline Quick Reference</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/operator/aggregation/interface.html">Aggregation Commands</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/aggregation-commands-comparison.html">Aggregation Commands Comparison</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/aggregation-variables.html">Variables in Aggregation Expressions</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/sql-aggregation-comparison.html">SQL to Aggregation Mapping Chart</a></li></ul></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../data-modeling.html">Data Models</a><ul><li class="toctree-l2"><a class="reference internal" href="../core/data-modeling-introduction.html">Data Modeling Introduction</a></li><li class="toctree-l2"><a class="reference internal" href="../core/schema-validation.html">Schema Validation</a></li><li class="toctree-l2"><a class="reference internal" href="../core/data-models.html">Data Modeling Concepts</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/data-model-design.html">Data Model Design</a></li><li class="toctree-l3"><a class="reference internal" href="../core/data-model-operations.html">Operational Factors and Data Models</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../applications/data-models.html">Data Model Examples and Patterns</a><ul><li class="toctree-l3"><a class="reference internal" href="../applications/data-models-relationships.html">Model Relationships Between Documents</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-embedded-one-to-one-relationships-between-documents.html">Model One-to-One Relationships with Embedded Documents</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-embedded-one-to-many-relationships-between-documents.html">Model One-to-Many Relationships with Embedded Documents</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-referenced-one-to-many-relationships-between-documents.html">Model One-to-Many Relationships with Document References</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../applications/data-models-tree-structures.html">Model Tree Structures</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-tree-structures-with-parent-references.html">Model Tree Structures with Parent References</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-tree-structures-with-child-references.html">Model Tree Structures with Child References</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-tree-structures-with-ancestors-array.html">Model Tree Structures with an Array of Ancestors</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-tree-structures-with-materialized-paths.html">Model Tree Structures with Materialized Paths</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-tree-structures-with-nested-sets.html">Model Tree Structures with Nested Sets</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../applications/data-models-applications.html">Model Specific Application Contexts</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-data-for-atomic-operations.html">Model Data for Atomic Operations</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-data-for-keyword-search.html">Model Data to Support Keyword Search</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-data-for-schema-versioning.html">Model Data for Schema Versioning</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-monetary-data.html">Model Monetary Data</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-time-data.html">Model Time Data</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-computed-data.html">Model Computed Data</a></li></ul></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/data-models.html">Data Model Reference</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/database-references.html">Database References</a></li></ul></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../core/transactions.html">Transactions</a><ul><li class="toctree-l2"><a class="reference internal" href="../core/transactions-in-applications.html">Drivers API</a></li><li class="toctree-l2"><a class="reference internal" href="../core/transactions-production-consideration.html">Production Considerations</a></li><li class="toctree-l2"><a class="reference internal" href="../core/transactions-sharded-clusters.html">Production Considerations (Sharded Clusters)</a></li><li class="toctree-l2"><a class="reference internal" href="../core/transactions-operations.html">Transactions and Operations</a></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../indexes.html">Indexes</a><ul><li class="toctree-l2"><a class="reference internal" href="../core/index-single.html">Single Field Indexes</a></li><li class="toctree-l2"><a class="reference internal" href="../core/index-compound.html">Compound Indexes</a></li><li class="toctree-l2"><a class="reference internal" href="../core/index-multikey.html">Multikey Indexes</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/multikey-index-bounds.html">Multikey Index Bounds</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/index-text.html">Text Indexes</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/specify-language-for-text-index.html">Specify a Language for Text Index</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/avoid-text-index-name-limit.html">Specify Name for <code class="docutils literal"><span class="pre">text</span></code> Index</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/control-results-of-text-search.html">Control Search Results with Weights</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/limit-number-of-items-scanned-for-text-search.html">Limit the Number of Entries Scanned</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/index-wildcard.html">Wildcard Indexes</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/index-wildcard-restrictions.html">Wildcard Index Restrictions</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/2dsphere.html"><code class="docutils literal"><span class="pre">2dsphere</span></code> Indexes</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/query-a-2dsphere-index.html">Query a <code class="docutils literal"><span class="pre">2dsphere</span></code> Index</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/2d.html"><code class="docutils literal"><span class="pre">2d</span></code> Indexes</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/build-a-2d-index.html">Create a <code class="docutils literal"><span class="pre">2d</span></code> Index</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/query-a-2d-index.html">Query a <code class="docutils literal"><span class="pre">2d</span></code> Index</a></li><li class="toctree-l3"><a class="reference internal" href="../core/geospatial-indexes.html"><code class="docutils literal"><span class="pre">2d</span></code> Index Internals</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/calculate-distances-using-spherical-geometry-with-2d-geospatial-indexes.html">Calculate Distance Using Spherical Geometry</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/geohaystack.html"><code class="docutils literal"><span class="pre">geoHaystack</span></code> Indexes</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/build-a-geohaystack-index.html">Create a Haystack Index</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/query-a-geohaystack-index.html">Query a Haystack Index</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/index-hashed.html">Hashed Indexes</a></li><li class="toctree-l2"><a class="reference internal" href="../core/index-properties.html">Index Properties</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/index-ttl.html">TTL Indexes</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/expire-data.html">Expire Data from Collections by Setting TTL</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/index-unique.html">Unique Indexes</a></li><li class="toctree-l3"><a class="reference internal" href="../core/index-partial.html">Partial Indexes</a></li><li class="toctree-l3"><a class="reference internal" href="../core/index-case-insensitive.html">Case Insensitive Indexes</a></li><li class="toctree-l3"><a class="reference internal" href="../core/index-sparse.html">Sparse Indexes</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/index-creation.html">Index Builds on Populated Collections</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/build-indexes-on-replica-sets.html">Build Indexes on Replica Sets</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/build-indexes-on-sharded-clusters.html">Build Indexes on Sharded Clusters</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/index-intersection.html">Index Intersection</a></li><li class="toctree-l2"><a class="reference internal" href="../tutorial/manage-indexes.html">Manage Indexes</a></li><li class="toctree-l2"><a class="reference internal" href="../tutorial/measure-index-use.html">Measure Index Use</a></li><li class="toctree-l2"><a class="reference internal" href="../applications/indexes.html">Indexing Strategies</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/create-indexes-to-support-queries.html">Create Indexes to Support Your Queries</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/sort-results-with-indexes.html">Use Indexes to Sort Query Results</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/ensure-indexes-fit-ram.html">Ensure Indexes Fit in RAM</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/create-queries-that-ensure-selectivity.html">Create Queries that Ensure Selectivity</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/indexes.html">Indexing Reference</a></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../security.html">Security</a><ul><li class="toctree-l2"><a class="reference internal" href="../administration/security-checklist.html">Security Checklist</a></li><li class="toctree-l2"><a class="reference internal" href="../tutorial/enable-authentication.html">Enable Access Control</a></li><li class="toctree-l2"><a class="reference internal" href="../core/authentication.html">Authentication</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/security-users.html">Users</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/create-users.html">Add Users</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/authentication-mechanisms.html">Authentication Mechanisms</a><ul><li class="toctree-l4"><a class="reference internal" href="../core/security-scram.html">SCRAM</a></li><li class="toctree-l4"><a class="reference internal" href="../core/security-x.509.html">x.509</a><ul><li class="toctree-l5"><a class="reference internal" href="../tutorial/configure-x509-client-authentication.html">Use x.509 Certificates to Authenticate Clients</a></li></ul></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/authentication-mechanisms-enterprise.html">Enterprise Authentication Mechanisms</a><ul><li class="toctree-l4"><a class="reference internal" href="../core/kerberos.html">Kerberos Authentication</a><ul><li class="toctree-l5"><a class="reference internal" href="../tutorial/control-access-to-mongodb-with-kerberos-authentication.html">Configure MongoDB with Kerberos Authentication on Linux</a></li><li class="toctree-l5"><a class="reference internal" href="../tutorial/control-access-to-mongodb-windows-with-kerberos-authentication.html">Configure MongoDB with Kerberos Authentication on Windows</a></li><li class="toctree-l5"><a class="reference internal" href="../tutorial/troubleshoot-kerberos.html">Troubleshoot Kerberos Authentication</a></li><li class="toctree-l5"><a class="reference internal" href="../tutorial/kerberos-auth-activedirectory-authz.html">Configure MongoDB with Kerberos Authentication and Active Directory Authorization</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../core/security-ldap.html">LDAP Proxy Authentication</a><ul><li class="toctree-l5"><a class="reference internal" href="../tutorial/configure-ldap-sasl-activedirectory.html">Authenticate Using SASL and LDAP with ActiveDirectory</a></li><li class="toctree-l5"><a class="reference internal" href="../tutorial/configure-ldap-sasl-openldap.html">Authenticate Using SASL and LDAP with OpenLDAP</a></li><li class="toctree-l5"><a class="reference internal" href="../tutorial/authenticate-nativeldap-activedirectory.html">Authenticate and Authorize Users Using Active Directory via Native LDAP</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../core/security-ldap-external.html">LDAP Authorization</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/security-internal-authentication.html">Internal/Membership Authentication</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/deploy-replica-set-with-keyfile-access-control.html">Deploy Replica Set With Keyfile Authentication</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/enforce-keyfile-access-control-in-existing-replica-set.html">Update Replica Set to Keyfile Authentication</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/enforce-keyfile-access-control-in-existing-replica-set-without-downtime.html">Update Replica Set to Keyfile Authentication (No Downtime)</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/rotate-key-replica-set.html">Rotate Keys for Replica Sets</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/deploy-sharded-cluster-with-keyfile-access-control.html">Deploy Sharded Cluster with Keyfile Authentication</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/enforce-keyfile-access-control-in-existing-sharded-cluster.html">Update Sharded Cluster to Keyfile Authentication</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/enforce-keyfile-access-control-in-existing-sharded-cluster-no-downtime.html">Update Sharded Cluster to Keyfile Authentication (No Downtime)</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/rotate-key-sharded-cluster.html">Rotate Keys for Sharded Clusters</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/configure-x509-member-authentication.html">Use x.509 Certificate for Membership Authentication</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/upgrade-keyfile-to-x509.html">Upgrade from Keyfile Authentication to x.509 Authentication</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/rotate-x509-membership-certificates.html">Rolling Update of x.509 Cluster Certificates that Contain New DN</a></li></ul></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/authorization.html">Role-Based Access Control</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/built-in-roles.html">Built-In Roles</a></li><li class="toctree-l3"><a class="reference internal" href="../core/security-user-defined-roles.html">User-Defined Roles</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-users-and-roles.html">Manage Users and Roles</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/change-own-password-and-custom-data.html">Change Your Password and Custom Data</a></li><li class="toctree-l3"><a class="reference internal" href="../core/collection-level-access-control.html">Collection-Level Access Control</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/security-transport-encryption.html">TLS/SSL (Transport Encryption)</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-ssl.html">Configure <code class="docutils literal"><span class="pre">mongod</span></code> and <code class="docutils literal"><span class="pre">mongos</span></code> for TLS/SSL</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-ssl-clients.html">TLS/SSL Configuration for Clients</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/upgrade-cluster-to-ssl.html">Upgrade a Cluster to Use TLS/SSL</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-fips.html">Configure MongoDB for FIPS</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/security-encryption-at-rest.html">Encryption at Rest</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-encryption.html">Configure Encryption</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/rotate-encryption-key.html">Rotate Encryption Keys</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/security-client-side-encryption.html">Client-Side Field Level Encryption</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/security-automatic-client-side-encryption.html">Automatic Client-Side Field Level Encryption</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/security-client-side-automatic-json-schema.html">Automatic Encryption Rules</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/security-client-side-query-aggregation-support.html">Read/Write Support with Automatic Field Level Encryption</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/security-client-side-encryption-appendix.html">Appendix</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/security-explicit-client-side-encryption.html">Explicit (Manual) Client-Side Field Level Encryption</a></li><li class="toctree-l3"><a class="reference internal" href="../core/security-client-side-encryption-key-management.html">Master Key and Data Encryption Key Management</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/manage-client-side-encryption-data-keys.html">Manage Data Encryption Keys</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/security-client-side-encryption-limitations.html">Limitations</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/auditing.html">Auditing</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-auditing.html">Configure Auditing</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-audit-filters.html">Configure Audit Filters</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/audit-message.html">System Event Audit Messages</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/security-hardening.html">Network and Configuration Hardening</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/security-mongodb-configuration.html">IP Binding</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-linux-iptables-firewall.html">Configure Linux <code class="docutils literal"><span class="pre">iptables</span></code> Firewall for MongoDB</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-windows-netsh-firewall.html">Configure Windows <code class="docutils literal"><span class="pre">netsh</span></code> Firewall for MongoDB</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../tutorial/implement-field-level-redaction.html">Implement Field Level Redaction</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/security.html">Security Reference</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/system-roles-collection.html"><code class="docutils literal"><span class="pre">system.roles</span></code> Collection</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/system-users-collection.html"><code class="docutils literal"><span class="pre">system.users</span></code> Collection</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/resource-document.html">Resource Document</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/privilege-actions.html">Privilege Actions</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../tutorial/create-a-vulnerability-report.html">Create a Vulnerability Report</a></li><li class="toctree-l2"><a class="reference internal" href="../appendix/security.html">Appendix</a><ul><li class="toctree-l3"><a class="reference internal" href="../appendix/security/appendixA-openssl-ca.html">Appendix A - OpenSSL CA Certificate for Testing</a></li><li class="toctree-l3"><a class="reference internal" href="../appendix/security/appendixB-openssl-server.html">Appendix B - OpenSSL Server Certificates for Testing</a></li><li class="toctree-l3"><a class="reference internal" href="../appendix/security/appendixC-openssl-client.html">Appendix C - OpenSSL Client Certificates for Testing</a></li></ul></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../changeStreams.html">Change Streams</a><ul><li class="toctree-l2"><a class="reference internal" href="../administration/change-streams-production-recommendations.html">Change Streams Production Recommendations</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/change-events.html">Change Events</a></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../replication.html">Replication</a><ul><li class="toctree-l2"><a class="reference internal" href="../core/replica-set-members.html">Replica Set Members</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-primary.html">Replica Set Primary</a></li><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-secondary.html">Replica Set Secondary Members</a><ul><li class="toctree-l4"><a class="reference internal" href="../core/replica-set-priority-0-member.html">Priority 0 Replica Set Members</a></li><li class="toctree-l4"><a class="reference internal" href="../core/replica-set-hidden-member.html">Hidden Replica Set Members</a></li><li class="toctree-l4"><a class="reference internal" href="../core/replica-set-delayed-member.html">Delayed Replica Set Members</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-arbiter.html">Replica Set Arbiter</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/replica-set-oplog.html">Replica Set Oplog</a></li><li class="toctree-l2"><a class="reference internal" href="../core/replica-set-sync.html">Replica Set Data Synchronization</a></li><li class="toctree-l2"><a class="reference internal" href="../core/replica-set-architectures.html">Replica Set Deployment Architectures</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-architecture-three-members.html">Three Member Replica Sets</a></li><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-architecture-geographically-distributed.html">Replica Sets Distributed Across Two or More Data Centers</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/replica-set-high-availability.html">Replica Set High Availability</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-elections.html">Replica Set Elections</a></li><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-rollbacks.html">Rollbacks During Replica Set Failover</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../applications/replication.html">Replica Set Read and Write Semantics</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-write-concern.html">Write Concern for Replica Sets</a></li><li class="toctree-l3"><a class="reference internal" href="../core/read-preference.html">Read Preference</a><ul><li class="toctree-l4"><a class="reference internal" href="../core/read-preference-tags.html">Tag Sets</a></li><li class="toctree-l4"><a class="reference internal" href="../core/read-preference-staleness.html">maxStalenessSeconds</a></li><li class="toctree-l4"><a class="reference internal" href="../core/read-preference-use-cases.html">Read Preference Use Cases</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/read-preference-mechanics.html">Server Selection Algorithm</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../administration/replica-set-deployment.html">Replica Set Deployment Tutorials</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/deploy-replica-set.html">Deploy a Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/deploy-replica-set-for-testing.html">Deploy a Replica Set for Testing and Development</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/deploy-geographically-distributed-replica-set.html">Deploy a Geographically Redundant Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/add-replica-set-arbiter.html">Add an Arbiter to Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/convert-standalone-to-replica-set.html">Convert a Standalone to a Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/expand-replica-set.html">Add Members to a Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/remove-replica-set-member.html">Remove Members from Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/replace-replica-set-member.html">Replace a Replica Set Member</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../administration/replica-set-member-configuration.html">Member Configuration Tutorials</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/adjust-replica-set-member-priority.html">Adjust Priority for Replica Set Member</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-secondary-only-replica-set-member.html">Prevent Secondary from Becoming Primary</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-a-hidden-replica-set-member.html">Configure a Hidden Replica Set Member</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-a-delayed-replica-set-member.html">Configure a Delayed Replica Set Member</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-a-non-voting-replica-set-member.html">Configure Non-Voting Replica Set Member</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/convert-secondary-into-arbiter.html">Convert a Secondary to an Arbiter</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../administration/replica-set-maintenance.html">Replica Set Maintenance Tutorials</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/change-oplog-size.html">Change the Size of the Oplog</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/perform-maintence-on-replica-set-members.html">Perform Maintenance on Replica Set Members</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/force-member-to-be-primary.html">Force a Member to Become Primary</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/resync-replica-set-member.html">Resync a Member of a Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-replica-set-tag-sets.html">Configure Replica Set Tag Sets</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/reconfigure-replica-set-with-unavailable-members.html">Reconfigure a Replica Set with Unavailable Members</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-chained-replication.html">Manage Chained Replication</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/change-hostnames-in-a-replica-set.html">Change Hostnames in a Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-replica-set-secondary-sync-target.html">Configure a Secondary’s Sync Target</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/replication.html">Replication Reference</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/replica-configuration.html">Replica Set Configuration</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/replica-set-protocol-versions.html">Replica Set Protocol Version</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/troubleshoot-replica-sets.html">Troubleshoot Replica Sets</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/local-database.html">The <code class="docutils literal"><span class="pre">local</span></code> Database</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/replica-states.html">Replica Set Member States</a></li></ul></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../sharding.html">Sharding</a><ul><li class="toctree-l2"><a class="reference internal" href="../core/sharded-cluster-components.html">Sharded Cluster Components</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/sharded-cluster-shards.html">Shards</a></li><li class="toctree-l3"><a class="reference internal" href="../core/sharded-cluster-config-servers.html">Config Servers (metadata)</a></li><li class="toctree-l3"><a class="reference internal" href="../core/sharded-cluster-query-router.html">Router (mongos)</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/sharding-shard-key.html">Shard Keys</a></li><li class="toctree-l2"><a class="reference internal" href="../core/hashed-sharding.html">Hashed Sharding</a></li><li class="toctree-l2"><a class="reference internal" href="../core/ranged-sharding.html">Ranged Sharding</a></li><li class="toctree-l2"><a class="reference internal" href="../tutorial/deploy-shard-cluster.html">Deploy a Sharded Cluster</a></li><li class="toctree-l2"><a class="reference internal" href="../core/zone-sharding.html">Zones</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-shard-zone.html">Manage Shard Zones</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/sharding-segmenting-data-by-location.html">Segmenting Data by Location</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/sharding-tiered-hardware-for-varying-slas.html">Tiered Hardware for Varying SLA or SLO</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/sharding-segmenting-shards.html">Segmenting Data by Application or Customer</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/sharding-high-availability-writes.html">Distributed Local Writes for Insert Only Workloads</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/sharding-data-partitioning.html">Data Partitioning with Chunks</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/create-chunks-in-sharded-cluster.html">Create Chunks in a Sharded Cluster</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/split-chunks-in-sharded-cluster.html">Split Chunks in a Sharded Cluster</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/merge-chunks-in-sharded-cluster.html">Merge Chunks in a Sharded Cluster</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/modify-chunk-size-in-sharded-cluster.html">Modify Chunk Size in a Sharded Cluster</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/sharding-balancer-administration.html">Balancer</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-sharded-cluster-balancer.html">Manage Sharded Cluster Balancer</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/migrate-chunks-in-sharded-cluster.html">Migrate Chunks in a Sharded Cluster</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../administration/sharded-cluster-administration.html">Administration</a><ul><li class="toctree-l3"><a class="reference internal" href="../administration/sharded-cluster-config-servers.html">Config Server Administration</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/replace-config-server.html">Replace a Config Server</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/view-sharded-cluster-configuration.html">View Cluster Configuration</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/restart-sharded-cluster.html">Restart a Sharded Cluster</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/migrate-sharded-cluster-to-new-hardware.html">Migrate a Sharded Cluster to Different Hardware</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/add-shards-to-shard-cluster.html">Add Shards to a Cluster</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/remove-shards-from-cluster.html">Remove Shards from an Existing Sharded Cluster</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/clear-jumbo-flag.html">Clear <code class="docutils literal"><span class="pre">jumbo</span></code> Flag</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/backup-sharded-cluster-metadata.html">Back Up Cluster Metadata</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/convert-sharded-cluster-to-replica-set.html">Convert Sharded Cluster to Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/convert-replica-set-to-replicated-shard-cluster.html">Convert a Replica Set to a Sharded Cluster</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/convert-shard-standalone-to-shard-replica-set.html">Convert a Shard Standalone to a Shard Replica Set</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/sharding.html">Sharding Reference</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/sharded-cluster-requirements.html">Operational Restrictions</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/troubleshoot-sharded-clusters.html">Troubleshoot Sharded Clusters</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/config-database.html">Config Database</a></li></ul></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../administration.html">Administration</a><ul><li class="toctree-l2"><a class="reference internal" href="../administration/production-notes.html">Production Notes</a></li><li class="toctree-l2"><a class="reference internal" href="../administration/production-checklist-operations.html">Operations Checklist</a></li><li class="toctree-l2"><a class="reference internal" href="../administration/production-checklist-development.html">Development Checklist</a></li><li class="toctree-l2"><a class="reference internal" href="../administration/analyzing-mongodb-performance.html">Performance</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-the-database-profiler.html">Database Profiler</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/database-profiler.html">Database Profiler Output</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/transparent-huge-pages.html">Disable Transparent Huge Pages (THP)</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/ulimit.html">UNIX <code class="docutils literal"><span class="pre">ulimit</span></code> Settings</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../administration/configuration-and-maintenance.html">Configuration and Maintenance</a><ul><li class="toctree-l3"><a class="reference internal" href="../administration/configuration.html">Run-time Database Configuration</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/upgrade-revision.html">Upgrade to the Latest Revision of MongoDB</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-mongodb-processes.html">Manage <code class="docutils literal"><span class="pre">mongod</span></code> Processes</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/terminate-running-operations.html">Terminate Running Operations</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/rotate-log-files.html">Rotate Log Files</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../data-center-awareness.html">Data Center Awareness</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/workload-isolation.html">Workload Isolation in MongoDB Deployments</a></li><li class="toctree-l3"><a class="reference internal" href="../core/zone-sharding.html">Zones</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/manage-shard-zone.html">Manage Shard Zones</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/sharding-segmenting-data-by-location.html">Segmenting Data by Location</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/sharding-tiered-hardware-for-varying-slas.html">Tiered Hardware for Varying SLA or SLO</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/sharding-segmenting-shards.html">Segmenting Data by Application or Customer</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/sharding-high-availability-writes.html">Distributed Local Writes for Insert Only Workloads</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-shard-zone.html">Manage Shard Zones</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/backups.html">MongoDB Backup Methods</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/backup-with-filesystem-snapshots.html">Back Up and Restore with Filesystem Snapshots</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/backup-and-restore-tools.html">Back Up and Restore with MongoDB Tools</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/restore-replica-set-from-backup.html">Restore a Replica Set from MongoDB Backups</a></li><li class="toctree-l3"><a class="reference internal" href="../administration/backup-sharded-clusters.html">Backup and Restore Sharded Clusters</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/backup-sharded-cluster-with-filesystem-snapshots.html">Back Up a Sharded Cluster with File System Snapshots</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/backup-sharded-cluster-with-database-dumps.html">Back Up a Sharded Cluster with Database Dumps</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/schedule-backup-window-for-sharded-clusters.html">Schedule Backup Window for Sharded Clusters</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/restore-sharded-cluster.html">Restore a Sharded Cluster</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/recover-data-following-unexpected-shutdown.html">Recover a Standalone after an Unexpected Shutdown</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../administration/monitoring.html">Monitoring for MongoDB</a><ul><li class="toctree-l3"><a class="reference internal" href="../administration/free-monitoring.html">Free Monitoring</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/monitor-with-snmp.html">Monitor MongoDB With SNMP on Linux</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/monitor-with-snmp-on-windows.html">Monitor MongoDB Windows with SNMP</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/troubleshoot-snmp.html">Troubleshoot SNMP</a></li></ul></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../storage.html">Storage</a><ul><li class="toctree-l2"><a class="reference internal" href="../core/storage-engines.html">Storage Engines</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/wiredtiger.html">WiredTiger Storage Engine</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/change-standalone-wiredtiger.html">Change Standalone to WiredTiger</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/change-replica-set-wiredtiger.html">Change Replica Set to WiredTiger</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/change-sharded-cluster-wiredtiger.html">Change Sharded Cluster to WiredTiger</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/inmemory.html">In-Memory Storage Engine</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/journaling.html">Journaling</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-journaling.html">Manage Journaling</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/gridfs.html">GridFS</a></li><li class="toctree-l2"><a class="reference internal" href="../faq/storage.html">FAQ: MongoDB Storage</a></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../faq.html">Frequently Asked Questions</a><ul><li class="toctree-l2"><a class="reference internal" href="../faq/fundamentals.html">FAQ: MongoDB Fundamentals</a></li><li class="toctree-l2"><a class="reference internal" href="../faq/indexes.html">FAQ: Indexes</a></li><li class="toctree-l2"><a class="reference internal" href="../faq/concurrency.html">FAQ: Concurrency</a></li><li class="toctree-l2"><a class="reference internal" href="../faq/sharding.html">FAQ: Sharding with MongoDB</a></li><li class="toctree-l2"><a class="reference internal" href="../faq/replica-sets.html">FAQ: Replication and Replica Sets</a></li><li class="toctree-l2"><a class="reference internal" href="../faq/storage.html">FAQ: MongoDB Storage</a></li><li class="toctree-l2"><a class="reference internal" href="../faq/diagnostics.html">FAQ: MongoDB Diagnostics</a></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../reference.html">Reference</a><ul><li class="toctree-l2"><a class="reference internal" href="../reference/operator.html">Operators</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/operator/query.html">Query and Projection Operators</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query-comparison.html">Comparison Query Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/eq.html">$eq</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/gt.html">$gt</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/gte.html">$gte</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/in.html">$in</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/lt.html">$lt</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/lte.html">$lte</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/ne.html">$ne</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/nin.html">$nin</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query-logical.html">Logical Query Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/and.html">$and</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/not.html">$not</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/nor.html">$nor</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/or.html">$or</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query-element.html">Element Query Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/exists.html">$exists</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/type.html">$type</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query-evaluation.html">Evaluation Query Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/expr.html">$expr</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/jsonSchema.html">$jsonSchema</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/mod.html">$mod</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/regex.html">$regex</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/text.html">$text</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/where.html">$where</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query-geospatial.html">Geospatial Query Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/geoIntersects.html">$geoIntersects</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/geoWithin.html">$geoWithin</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/near.html">$near</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/nearSphere.html">$nearSphere</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/box.html">$box</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/center.html">$center</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/centerSphere.html">$centerSphere</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/geometry.html">$geometry</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/maxDistance.html">$maxDistance</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/minDistance.html">$minDistance</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/polygon.html">$polygon</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/uniqueDocs.html">$uniqueDocs</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query-array.html">Array Query Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/all.html">$all</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/elemMatch.html">$elemMatch (query)</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/size.html">$size</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query-bitwise.html">Bitwise Query Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/bitsAllClear.html">$bitsAllClear</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/bitsAllSet.html">$bitsAllSet</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/bitsAnyClear.html">$bitsAnyClear</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/bitsAnySet.html">$bitsAnySet</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query/comment.html">$comment</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/projection.html">Projection Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/projection/positional.html">$ (projection)</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/projection/elemMatch.html">$elemMatch (projection)</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/projection/meta.html">$meta</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/projection/slice.html">$slice (projection)</a></li></ul></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/operator/update.html">Update Operators</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/operator/update-field.html">Field Update Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/currentDate.html">$currentDate</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/inc.html">$inc</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/min.html">$min</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/max.html">$max</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/mul.html">$mul</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/rename.html">$rename</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/set.html">$set</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/setOnInsert.html">$setOnInsert</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/unset.html">$unset</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/update-array.html">Array Update Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/positional.html">$ (update)</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/positional-all.html">$[]</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/positional-filtered.html">$[&lt;identifier&gt;]</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/addToSet.html">$addToSet</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/pop.html">$pop</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/pull.html">$pull</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/push.html">$push</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/pullAll.html">$pullAll</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/each.html">$each</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/position.html">$position</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/slice.html">$slice</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/sort.html">$sort</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/update-bitwise.html">Bitwise Update Operator</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/bit.html">$bit</a></li></ul></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/operator/aggregation-pipeline.html">Aggregation Pipeline Stages</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/addFields.html">$addFields (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/bucket.html">$bucket (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/bucketAuto.html">$bucketAuto (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/collStats.html">$collStats (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/count.html">$count (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/currentOp.html">$currentOp (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/facet.html">$facet (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/geoNear.html">$geoNear (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/graphLookup.html">$graphLookup (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/group.html">$group (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/indexStats.html">$indexStats (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/limit.html">$limit (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/listLocalSessions.html">$listLocalSessions</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/listSessions.html">$listSessions</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/lookup.html">$lookup (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/match.html">$match (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/merge.html">$merge (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/out.html">$out (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/planCacheStats.html">$planCacheStats</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/project.html">$project (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/redact.html">$redact (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/replaceRoot.html">$replaceRoot (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/replaceWith.html">$replaceWith (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/sample.html">$sample (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/set.html">$set (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/skip.html">$skip (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/sort.html">$sort (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/sortByCount.html">$sortByCount (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/unset.html">$unset (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/unwind.html">$unwind (aggregation)</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/operator/aggregation.html">Aggregation Pipeline Operators</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/abs.html">$abs (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/acos.html">$acos (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/acosh.html">$acosh (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/add.html">$add (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/addToSet.html">$addToSet (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/allElementsTrue.html">$allElementsTrue (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/and.html">$and (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/anyElementTrue.html">$anyElementTrue (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/arrayElemAt.html">$arrayElemAt (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/arrayToObject.html">$arrayToObject (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/asin.html">$asin (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/asinh.html">$asinh (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/atan.html">$atan (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/atan2.html">$atan2 (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/atanh.html">$atanh (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/avg.html">$avg (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/ceil.html">$ceil (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/cmp.html">$cmp (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/concat.html">$concat (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/concatArrays.html">$concatArrays (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/cond.html">$cond (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/convert.html">$convert (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/cos.html">$cos (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/dateFromParts.html">$dateFromParts (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/dateToParts.html">$dateToParts (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/dateFromString.html">$dateFromString (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/dateToString.html">$dateToString (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/dayOfMonth.html">$dayOfMonth (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/dayOfWeek.html">$dayOfWeek (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/dayOfYear.html">$dayOfYear (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/degreesToRadians.html">$degreesToRadians (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/divide.html">$divide (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/eq.html">$eq (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/exp.html">$exp (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/filter.html">$filter (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/first.html">$first (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/floor.html">$floor (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/gt.html">$gt (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/gte.html">$gte (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/hour.html">$hour (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/ifNull.html">$ifNull (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/in.html">$in (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/indexOfArray.html">$indexOfArray (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/indexOfBytes.html">$indexOfBytes (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/indexOfCP.html">$indexOfCP (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/isArray.html">$isArray (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/isoDayOfWeek.html">$isoDayOfWeek (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/isoWeek.html">$isoWeek (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/isoWeekYear.html">$isoWeekYear (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/last.html">$last (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/let.html">$let (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/literal.html">$literal (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/ln.html">$ln (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/log.html">$log (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/log10.html">$log10 (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/lt.html">$lt (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/lte.html">$lte (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/ltrim.html">$ltrim (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/map.html">$map (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/max.html">$max (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/mergeObjects.html">$mergeObjects (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/meta.html">$meta (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/min.html">$min (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/millisecond.html">$millisecond (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/minute.html">$minute (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/mod.html">$mod (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/month.html">$month (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/multiply.html">$multiply (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/ne.html">$ne (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/not.html">$not (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/objectToArray.html">$objectToArray (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/or.html">$or (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/pow.html">$pow (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/push.html">$push (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/radiansToDegrees.html">$radiansToDegrees (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/range.html">$range (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/reduce.html">$reduce (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/regexFind.html">$regexFind (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/regexFindAll.html">$regexFindAll (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/regexMatch.html">$regexMatch (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/reverseArray.html">$reverseArray (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/round.html">$round (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/rtrim.html">$rtrim (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/second.html">$second (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/setDifference.html">$setDifference (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/setEquals.html">$setEquals (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/setIntersection.html">$setIntersection (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/setIsSubset.html">$setIsSubset (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/setUnion.html">$setUnion (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/size.html">$size (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/sin.html">$sin (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/slice.html">$slice (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/split.html">$split (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/sqrt.html">$sqrt (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/stdDevPop.html">$stdDevPop (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/stdDevSamp.html">$stdDevSamp (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/strcasecmp.html">$strcasecmp (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/strLenBytes.html">$strLenBytes (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/strLenCP.html">$strLenCP (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/substr.html">$substr (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/substrBytes.html">$substrBytes (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/substrCP.html">$substrCP (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/subtract.html">$subtract (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/sum.html">$sum (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/switch.html">$switch (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/tan.html">$tan (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toBool.html">$toBool (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toDate.html">$toDate (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toDecimal.html">$toDecimal (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toDouble.html">$toDouble(aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toInt.html">$toInt (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toLong.html">$toLong (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toObjectId.html">$toObjectId (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toString.html">$toString (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toLower.html">$toLower (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toUpper.html">$toUpper (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/trim.html">$trim (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/trunc.html">$trunc (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/type.html">$type (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/week.html">$week (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/year.html">$year (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/zip.html">$zip (aggregation)</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/operator/query-modifier.html">Query Modifiers</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/comment.html">$comment</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/explain.html">$explain</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/hint.html">$hint</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/max.html">$max</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/maxTimeMS.html">$maxTimeMS</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/min.html">$min</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/orderby.html">$orderby</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/query.html">$query</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/returnKey.html">$returnKey</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/showDiskLoc.html">$showDiskLoc</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/natural.html">$natural</a></li></ul></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/command.html">Database Commands</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-aggregation.html">Aggregation Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/aggregate.html">aggregate</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/count.html">count</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/distinct.html">distinct</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/mapReduce.html">mapReduce</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-geospatial.html">Geospatial Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/geoSearch.html">geoSearch</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-crud.html">Query and Write Operation Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/delete.html">delete</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/find.html">find</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/findAndModify.html">findAndModify</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getLastError.html">getLastError</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getMore.html">getMore</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/insert.html">insert</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/resetError.html">resetError</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/update.html">update</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-plan-cache.html">Query Plan Cache Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/planCacheClear.html">planCacheClear</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/planCacheClearFilters.html">planCacheClearFilters</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/planCacheListFilters.html">planCacheListFilters</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/planCacheListPlans.html">planCacheListPlans</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/planCacheListQueryShapes.html">planCacheListQueryShapes</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/planCacheSetFilter.html">planCacheSetFilter</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-authentication.html">Authentication Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/authenticate.html">authenticate</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getnonce.html">getnonce</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/logout.html">logout</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-user-management.html">User Management Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/createUser.html">createUser</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dropAllUsersFromDatabase.html">dropAllUsersFromDatabase</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dropUser.html">dropUser</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/grantRolesToUser.html">grantRolesToUser</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/revokeRolesFromUser.html">revokeRolesFromUser</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/updateUser.html">updateUser</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/usersInfo.html">usersInfo</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-role-management.html">Role Management Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/createRole.html">createRole</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dropRole.html">dropRole</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dropAllRolesFromDatabase.html">dropAllRolesFromDatabase</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/grantPrivilegesToRole.html">grantPrivilegesToRole</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/grantRolesToRole.html">grantRolesToRole</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/invalidateUserCache.html">invalidateUserCache</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/revokePrivilegesFromRole.html">revokePrivilegesFromRole</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/revokeRolesFromRole.html">revokeRolesFromRole</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/rolesInfo.html">rolesInfo</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/updateRole.html">updateRole</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-replication.html">Replication Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/applyOps.html">applyOps</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/isMaster.html">isMaster</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetAbortPrimaryCatchUp.html">replSetAbortPrimaryCatchUp</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetFreeze.html">replSetFreeze</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetGetConfig.html">replSetGetConfig</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetGetStatus.html">replSetGetStatus</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetInitiate.html">replSetInitiate</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetMaintenance.html">replSetMaintenance</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetReconfig.html">replSetReconfig</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetResizeOplog.html">replSetResizeOplog</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetStepDown.html">replSetStepDown</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetSyncFrom.html">replSetSyncFrom</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-sharding.html">Sharding Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/addShard.html">addShard</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/addShardToZone.html">addShardToZone</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/balancerStart.html">balancerStart</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/balancerStatus.html">balancerStatus</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/balancerStop.html">balancerStop</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/checkShardingIndex.html">checkShardingIndex</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/clearJumboFlag.html">clearJumboFlag</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/cleanupOrphaned.html">cleanupOrphaned</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/enableSharding.html">enableSharding</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/flushRouterConfig.html">flushRouterConfig</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getShardMap.html">getShardMap</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getShardVersion.html">getShardVersion</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/isdbgrid.html">isdbgrid</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/listShards.html">listShards</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/medianKey.html">medianKey</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/moveChunk.html">moveChunk</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/movePrimary.html">movePrimary</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/mergeChunks.html">mergeChunks</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/removeShard.html">removeShard</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/removeShardFromZone.html">removeShardFromZone</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/setShardVersion.html">setShardVersion</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/shardCollection.html">shardCollection</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/shardingState.html">shardingState</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/split.html">split</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/splitChunk.html">splitChunk</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/splitVector.html">splitVector</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/unsetSharding.html">unsetSharding</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/updateZoneKeyRange.html">updateZoneKeyRange</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-sessions.html">Sessions Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/abortTransaction.html">abortTransaction</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/commitTransaction.html">commitTransaction</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/endSessions.html">endSessions</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/killAllSessions.html">killAllSessions</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/killAllSessionsByPattern.html">killAllSessionsByPattern</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/killSessions.html">killSessions</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/refreshSessions.html">refreshSessions</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/startSession.html">startSession</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-administration.html">Administration Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/clean.html">clean</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/cloneCollection.html">cloneCollection</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/cloneCollectionAsCapped.html">cloneCollectionAsCapped</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/collMod.html">collMod</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/compact.html">compact</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/connPoolSync.html">connPoolSync</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/convertToCapped.html">convertToCapped</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/create.html">create</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/createIndexes.html">createIndexes</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/currentOp.html">currentOp</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/drop.html">drop</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dropDatabase.html">dropDatabase</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dropConnections.html">dropConnections</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dropIndexes.html">dropIndexes</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/filemd5.html">filemd5</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/fsync.html">fsync</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/fsyncUnlock.html">fsyncUnlock</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getParameter.html">getParameter</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/killCursors.html">killCursors</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/killOp.html">killOp</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/listCollections.html">listCollections</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/listDatabases.html">listDatabases</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/listIndexes.html">listIndexes</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/logRotate.html">logRotate</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/reIndex.html">reIndex</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/renameCollection.html">renameCollection</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/setFeatureCompatibilityVersion.html">setFeatureCompatibilityVersion</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/setParameter.html">setParameter</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/shutdown.html">shutdown</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-diagnostic.html">Diagnostic Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/availableQueryOptions.html">availableQueryOptions</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/buildInfo.html">buildInfo</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/collStats.html">collStats</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/connPoolStats.html">connPoolStats</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/connectionStatus.html">connectionStatus</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/cursorInfo.html">cursorInfo</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dataSize.html">dataSize</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dbHash.html">dbHash</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dbStats.html">dbStats</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/diagLogging.html">diagLogging</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/driverOIDTest.html">driverOIDTest</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/explain.html">explain</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/features.html">features</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getCmdLineOpts.html">getCmdLineOpts</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getLog.html">getLog</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/hostInfo.html">hostInfo</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/isSelf.html">isSelf</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/listCommands.html">listCommands</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/netstat.html">netstat</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/ping.html">ping</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/profile.html">profile</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/serverStatus.html">serverStatus</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/shardConnPoolStats.html">shardConnPoolStats</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/top.html">top</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/validate.html">validate</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/whatsmyuri.html">whatsmyuri</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-free-monitoring.html">Free Monitoring Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/getFreeMonitoringStatus.html">getFreeMonitoringStatus</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/setFreeMonitoring.html">setFreeMonitoring</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-auditing.html">System Events Auditing Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/logApplicationMessage.html">logApplicationMessage</a></li></ul></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/method.html"><code class="docutils literal"><span class="pre">mongo</span></code> Shell Methods</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-collection.html">Collection Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.aggregate.html">db.collection.aggregate()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.bulkWrite.html">db.collection.bulkWrite()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.copyTo.html">db.collection.copyTo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.count.html">db.collection.count()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.countDocuments.html">db.collection.countDocuments()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.estimatedDocumentCount.html">db.collection.estimatedDocumentCount()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.createIndex.html">db.collection.createIndex()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.createIndexes.html">db.collection.createIndexes()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.dataSize.html">db.collection.dataSize()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.deleteOne.html">db.collection.deleteOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.deleteMany.html">db.collection.deleteMany()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.distinct.html">db.collection.distinct()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.drop.html">db.collection.drop()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.dropIndex.html">db.collection.dropIndex()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.dropIndexes.html">db.collection.dropIndexes()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.ensureIndex.html">db.collection.ensureIndex()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.explain.html">db.collection.explain()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.find.html">db.collection.find()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.findAndModify.html">db.collection.findAndModify()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.findOne.html">db.collection.findOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.findOneAndDelete.html">db.collection.findOneAndDelete()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.findOneAndReplace.html">db.collection.findOneAndReplace()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.findOneAndUpdate.html">db.collection.findOneAndUpdate()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.getIndexes.html">db.collection.getIndexes()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.getShardDistribution.html">db.collection.getShardDistribution()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.getShardVersion.html">db.collection.getShardVersion()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.insert.html">db.collection.insert()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.insertOne.html">db.collection.insertOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.insertMany.html">db.collection.insertMany()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.isCapped.html">db.collection.isCapped()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.latencyStats.html">db.collection.latencyStats()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.mapReduce.html">db.collection.mapReduce()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.reIndex.html">db.collection.reIndex()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.remove.html">db.collection.remove()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.renameCollection.html">db.collection.renameCollection()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.replaceOne.html">db.collection.replaceOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.save.html">db.collection.save()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.stats.html">db.collection.stats()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.storageSize.html">db.collection.storageSize()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.totalIndexSize.html">db.collection.totalIndexSize()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.totalSize.html">db.collection.totalSize()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.update.html">db.collection.update()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.updateOne.html">db.collection.updateOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.updateMany.html">db.collection.updateMany()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.watch.html">db.collection.watch()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.validate.html">db.collection.validate()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-cursor.html">Cursor Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.addOption.html">cursor.addOption()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.allowPartialResults.html">cursor.allowPartialResults()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.batchSize.html">cursor.batchSize()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.close.html">cursor.close()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.isClosed.html">cursor.isClosed()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.collation.html">cursor.collation()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.comment.html">cursor.comment()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.count.html">cursor.count()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.explain.html">cursor.explain()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.forEach.html">cursor.forEach()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.hasNext.html">cursor.hasNext()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.hint.html">cursor.hint()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.isExhausted.html">cursor.isExhausted()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.itcount.html">cursor.itcount()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.limit.html">cursor.limit()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.map.html">cursor.map()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.max.html">cursor.max()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.maxTimeMS.html">cursor.maxTimeMS()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.min.html">cursor.min()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.next.html">cursor.next()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.noCursorTimeout.html">cursor.noCursorTimeout()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.objsLeftInBatch.html">cursor.objsLeftInBatch()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.pretty.html">cursor.pretty()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.readConcern.html">cursor.readConcern()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.readPref.html">cursor.readPref()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.returnKey.html">cursor.returnKey()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.showRecordId.html">cursor.showRecordId()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.size.html">cursor.size()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.skip.html">cursor.skip()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.sort.html">cursor.sort()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.tailable.html">cursor.tailable()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.toArray.html">cursor.toArray()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-database.html">Database Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.adminCommand.html">db.adminCommand()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.aggregate.html">db.aggregate()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.cloneCollection.html">db.cloneCollection()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.cloneDatabase.html">db.cloneDatabase()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.commandHelp.html">db.commandHelp()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.copyDatabase.html">db.copyDatabase()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.createCollection.html">db.createCollection()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.createView.html">db.createView()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.currentOp.html">db.currentOp()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.dropDatabase.html">db.dropDatabase()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.eval.html">db.eval()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.fsyncLock.html">db.fsyncLock()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.fsyncUnlock.html">db.fsyncUnlock()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getCollection.html">db.getCollection()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getCollectionInfos.html">db.getCollectionInfos()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getCollectionNames.html">db.getCollectionNames()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getLastError.html">db.getLastError()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getLastErrorObj.html">db.getLastErrorObj()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getLogComponents.html">db.getLogComponents()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getMongo.html">db.getMongo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getName.html">db.getName()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getProfilingLevel.html">db.getProfilingLevel()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getProfilingStatus.html">db.getProfilingStatus()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getReplicationInfo.html">db.getReplicationInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getSiblingDB.html">db.getSiblingDB()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.help.html">db.help()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.hostInfo.html">db.hostInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.isMaster.html">db.isMaster()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.killOp.html">db.killOp()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.listCommands.html">db.listCommands()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.logout.html">db.logout()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.printCollectionStats.html">db.printCollectionStats()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.printReplicationInfo.html">db.printReplicationInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.printShardingStatus.html">db.printShardingStatus()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.printSlaveReplicationInfo.html">db.printSlaveReplicationInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.resetError.html">db.resetError()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.runCommand.html">db.runCommand()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.serverBuildInfo.html">db.serverBuildInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.serverCmdLineOpts.html">db.serverCmdLineOpts()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.serverStatus.html">db.serverStatus()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.setLogLevel.html">db.setLogLevel()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.setProfilingLevel.html">db.setProfilingLevel()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.shutdownServer.html">db.shutdownServer()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.stats.html">db.stats()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.version.html">db.version()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.watch.html">db.watch()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-plan-cache.html">Query Plan Cache Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.getPlanCache.html">db.collection.getPlanCache()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/PlanCache.clear.html">PlanCache.clear()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/PlanCache.clearPlansByQuery.html">PlanCache.clearPlansByQuery()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/PlanCache.getPlansByQuery.html">PlanCache.getPlansByQuery()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/PlanCache.help.html">PlanCache.help()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/PlanCache.listQueryShapes.html">PlanCache.listQueryShapes()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-bulk.html">Bulk Operation Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.initializeOrderedBulkOp.html">db.collection.initializeOrderedBulkOp()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.initializeUnorderedBulkOp.html">db.collection.initializeUnorderedBulkOp()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.html">Bulk()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.execute.html">Bulk.execute()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.html">Bulk.find()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.arrayFilters.html">Bulk.find.arrayFilters()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.collation.html">Bulk.find.collation()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.hint.html">Bulk.find.hint()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.remove.html">Bulk.find.remove()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.removeOne.html">Bulk.find.removeOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.replaceOne.html">Bulk.find.replaceOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.updateOne.html">Bulk.find.updateOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.update.html">Bulk.find.update()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.upsert.html">Bulk.find.upsert()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.getOperations.html">Bulk.getOperations()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.insert.html">Bulk.insert()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.tojson.html">Bulk.tojson()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.toString.html">Bulk.toString()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-user-management.html">User Management Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.auth.html">db.auth()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.changeUserPassword.html">db.changeUserPassword()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.createUser.html">db.createUser()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.dropUser.html">db.dropUser()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.dropAllUsers.html">db.dropAllUsers()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getUser.html">db.getUser()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getUsers.html">db.getUsers()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.grantRolesToUser.html">db.grantRolesToUser()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.removeUser.html">db.removeUser()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.revokeRolesFromUser.html">db.revokeRolesFromUser()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.updateUser.html">db.updateUser()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/passwordPrompt.html">passwordPrompt()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-role-management.html">Role Management Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.createRole.html">db.createRole()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.dropRole.html">db.dropRole()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.dropAllRoles.html">db.dropAllRoles()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getRole.html">db.getRole()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getRoles.html">db.getRoles()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.grantPrivilegesToRole.html">db.grantPrivilegesToRole()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.revokePrivilegesFromRole.html">db.revokePrivilegesFromRole()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.grantRolesToRole.html">db.grantRolesToRole()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.revokeRolesFromRole.html">db.revokeRolesFromRole()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.updateRole.html">db.updateRole()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-replication.html">Replication Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.add.html">rs.add()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.addArb.html">rs.addArb()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.conf.html">rs.conf()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.freeze.html">rs.freeze()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.help.html">rs.help()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.initiate.html">rs.initiate()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.printReplicationInfo.html">rs.printReplicationInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.printSlaveReplicationInfo.html">rs.printSlaveReplicationInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.reconfig.html">rs.reconfig()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.remove.html">rs.remove()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.slaveOk.html">rs.slaveOk()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.status.html">rs.status()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.stepDown.html">rs.stepDown()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.syncFrom.html">rs.syncFrom()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-sharding.html">Sharding Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.addShard.html">sh.addShard()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.addShardTag.html">sh.addShardTag()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.addShardToZone.html">sh.addShardToZone()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.addTagRange.html">sh.addTagRange()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.disableBalancing.html">sh.disableBalancing()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.enableBalancing.html">sh.enableBalancing()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.disableAutoSplit.html">sh.disableAutoSplit</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.enableAutoSplit.html">sh.enableAutoSplit</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.enableSharding.html">sh.enableSharding()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.getBalancerHost.html">sh.getBalancerHost()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.getBalancerState.html">sh.getBalancerState()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.removeTagRange.html">sh.removeTagRange()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.removeRangeFromZone.html">sh.removeRangeFromZone()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.help.html">sh.help()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.isBalancerRunning.html">sh.isBalancerRunning()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.moveChunk.html">sh.moveChunk()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.removeShardTag.html">sh.removeShardTag()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.removeShardFromZone.html">sh.removeShardFromZone()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.setBalancerState.html">sh.setBalancerState()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.shardCollection.html">sh.shardCollection()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.splitAt.html">sh.splitAt()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.splitFind.html">sh.splitFind()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.startBalancer.html">sh.startBalancer()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.status.html">sh.status()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.stopBalancer.html">sh.stopBalancer()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.waitForBalancer.html">sh.waitForBalancer()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.waitForBalancerOff.html">sh.waitForBalancerOff()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.waitForPingChange.html">sh.waitForPingChange()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.updateZoneKeyRange.html">sh.updateZoneKeyRange()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/convertShardKeyToHashed.html">convertShardKeyToHashed</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-free-monitoring.html">Free Monitoring Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.disableFreeMonitoring.html">db.disableFreeMonitoring()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.enableFreeMonitoring.html">db.enableFreeMonitoring()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getFreeMonitoringStatus.html">db.getFreeMonitoringStatus</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-constructor.html">Object Constructors and Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/BulkWriteResult.html">BulkWriteResult()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Date.html">Date()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/ObjectId.html">ObjectId</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/ObjectId.getTimestamp.html">ObjectId.getTimestamp()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/ObjectId.toString.html">ObjectId.toString()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/ObjectId.valueOf.html">ObjectId.valueOf()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/UUID.html">UUID()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/WriteResult.html">WriteResult()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/WriteResult.hasWriteError.html">WriteResult.hasWriteError()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/WriteResult.hasWriteConcernError.html">WriteResult.hasWriteConcernError()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-connection.html">Connection Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/connect.html">connect()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.html">Mongo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.getDB.html">Mongo.getDB()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.getReadPrefMode.html">Mongo.getReadPrefMode()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.getReadPrefTagSet.html">Mongo.getReadPrefTagSet()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.isCausalConsistency.html">Mongo.isCausalConsistency()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.setCausalConsistency.html">Mongo.setCausalConsistency()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.setReadPref.html">Mongo.setReadPref()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.setSlaveOk.html">Mongo.setSlaveOk()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.startSession.html">Mongo.startSession()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.watch.html">Mongo.watch()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Session.html">Session</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/method/Session.abortTransaction.html">Session.abortTransaction()</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/method/Session.commitTransaction.html">Session.commitTransaction()</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/method/Session.startTransaction.html">Session.startTransaction()</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/SessionOptions.html">SessionOptions</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-native.html">Native Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/cat.html">cat()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cd.html">cd()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/copyDbpath.html">copyDbpath()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/getHostName.html">getHostName()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/getMemInfo.html">getMemInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/hostname.html">hostname()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/isInteractive.html">isInteractive()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/listFiles.html">listFiles()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/load.html">load()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/ls.html">ls()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/md5sumFile.html">md5sumFile()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/mkdir.html">mkdir()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/pwd.html">pwd()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/quit.html">quit()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/removeFile.html">removeFile()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/resetDbpath.html">resetDbpath()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sleep.html">sleep()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/setVerboseShell.html">setVerboseShell()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/version.html">version()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/isWindows.html">_isWindows()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rand.html">_rand()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-client-side-field-level-encryption.html">Client-Side Field Level Encryption Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/getKeyVault.html">getKeyVault()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/KeyVault.createKey.html">KeyVault.createKey()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/KeyVault.deleteKey.html">KeyVault.deleteKey()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/KeyVault.getKey.html">KeyVault.getKey()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/KeyVault.getKeys.html">KeyVault.getKeys()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/KeyVault.addKeyAlternateName.html">KeyVault.addKeyAlternateName()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/KeyVault.removeKeyAlternateName.html">KeyVault.removeKeyAlternateName()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/KeyVault.getKeyByAltName.html">KeyVault.getKeyByAltName()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/getClientEncryption.html">getClientEncryption()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/ClientEncryption.encrypt.html">ClientEncryption.encrypt()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/ClientEncryption.decrypt.html">ClientEncryption.decrypt()</a></li></ul></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/program.html">MongoDB Package Components</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongod.html"><code class="docutils literal"><span class="pre">mongod</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongos.html"><code class="docutils literal"><span class="pre">mongos</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongo.html"><code class="docutils literal"><span class="pre">mongo</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongod.exe.html"><code class="docutils literal"><span class="pre">mongod.exe</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongos.exe.html"><code class="docutils literal"><span class="pre">mongos.exe</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongodump.html"><code class="docutils literal"><span class="pre">mongodump</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongorestore.html"><code class="docutils literal"><span class="pre">mongorestore</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/bsondump.html"><code class="docutils literal"><span class="pre">bsondump</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongoimport.html"><code class="docutils literal"><span class="pre">mongoimport</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongoexport.html"><code class="docutils literal"><span class="pre">mongoexport</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongostat.html"><code class="docutils literal"><span class="pre">mongostat</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongotop.html"><code class="docutils literal"><span class="pre">mongotop</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongoreplay.html"><code class="docutils literal"><span class="pre">mongoreplay</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongoldap.html"><code class="docutils literal"><span class="pre">mongoldap</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongofiles.html"><code class="docutils literal"><span class="pre">mongofiles</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/install_compass.html"><code class="docutils literal"><span class="pre">install_compass</span></code></a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/configuration-options.html">Configuration File Options</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/expansion-directives.html">Externally Sourced Configuration File Values</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/convert-command-line-options-to-yaml.html">Convert Command-Line Options to YAML</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/configuration-file-settings-command-line-options-mapping.html">Configuration File Settings and Command-Line Options Mapping</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/parameters.html">MongoDB Server Parameters</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/limits.html">MongoDB Limits and Thresholds</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/explain-results.html">Explain Results</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/system-collections.html">System Collections</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/connection-string.html">Connection String URI Format</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/collation.html">Collation</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/collation-locales-defaults.html">Collation Locales and Default Parameters</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/mongodb-wire-protocol.html">MongoDB Wire Protocol</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/log-messages.html">Log Messages</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/exit-codes.html">Exit Codes and Statuses</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/glossary.html">Glossary</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/default-mongodb-port.html">Default MongoDB Port</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/server-sessions.html">Server Sessions</a></li></ul></li><li class="toctree-l1 current"><a class="reference internal" href="../release-notes.html">Release Notes</a><ul class="current"><li class="toctree-l2"><a class="reference internal" href="4.2.html">Release Notes for MongoDB 4.2</a><ul><li class="toctree-l3"><a class="reference internal" href="4.2-compatibility.html">Compatibility Changes in MongoDB 4.2</a></li><li class="toctree-l3"><a class="reference internal" href="4.2-upgrade-standalone.html">Upgrade a Standalone to 4.2</a></li><li class="toctree-l3"><a class="reference internal" href="4.2-upgrade-replica-set.html">Upgrade a Replica Set to 4.2</a></li><li class="toctree-l3"><a class="reference internal" href="4.2-upgrade-sharded-cluster.html">Upgrade a Sharded Cluster to 4.2</a></li><li class="toctree-l3"><a class="reference internal" href="4.2-downgrade.html">Downgrade 4.2 to 4.0</a><ul><li class="toctree-l4"><a class="reference internal" href="4.2-downgrade-standalone.html">Downgrade 4.2 Standalone to 4.0</a></li><li class="toctree-l4"><a class="reference internal" href="4.2-downgrade-replica-set.html">Downgrade 4.2 Replica Set to 4.0</a></li><li class="toctree-l4"><a class="reference internal" href="4.2-downgrade-sharded-cluster.html">Downgrade 4.2 Sharded Cluster to 4.0</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="4.2-changelog.html">4.2 Changelog</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="4.0.html">Release Notes for MongoDB 4.0</a><ul><li class="toctree-l3"><a class="reference internal" href="4.0-compatibility.html">Compatibility Changes in MongoDB 4.0</a></li><li class="toctree-l3"><a class="reference internal" href="4.0-upgrade-standalone.html">Upgrade a Standalone to 4.0</a></li><li class="toctree-l3"><a class="reference internal" href="4.0-upgrade-replica-set.html">Upgrade a Replica Set to 4.0</a></li><li class="toctree-l3"><a class="reference internal" href="4.0-upgrade-sharded-cluster.html">Upgrade a Sharded Cluster to 4.0</a></li><li class="toctree-l3"><a class="reference internal" href="4.0-downgrade-standalone.html">Downgrade 4.0 Standalone to 3.6</a></li><li class="toctree-l3"><a class="reference internal" href="4.0-downgrade-replica-set.html">Downgrade 4.0 Replica Set to 3.6</a></li><li class="toctree-l3"><a class="reference internal" href="4.0-downgrade-sharded-cluster.html">Downgrade 4.0 Sharded Cluster to 3.6</a></li><li class="toctree-l3"><a class="reference internal" href="4.0-changelog.html">4.0 Changelog</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="3.6.html">Release Notes for MongoDB 3.6</a><ul><li class="toctree-l3"><a class="reference internal" href="3.6-changelog.html">3.6 Changelog</a></li><li class="toctree-l3"><a class="reference internal" href="3.6-compatibility.html">Compatibility Changes in MongoDB 3.6</a></li><li class="toctree-l3"><a class="reference internal" href="3.6-upgrade-standalone.html">Upgrade a Standalone to 3.6</a></li><li class="toctree-l3"><a class="reference internal" href="3.6-upgrade-replica-set.html">Upgrade a Replica Set to 3.6</a></li><li class="toctree-l3"><a class="reference internal" href="3.6-upgrade-sharded-cluster.html">Upgrade a Sharded Cluster to 3.6</a></li><li class="toctree-l3"><a class="reference internal" href="3.6-downgrade-standalone.html">Downgrade 3.6 Standalone to 3.4</a></li><li class="toctree-l3"><a class="reference internal" href="3.6-downgrade-replica-set.html">Downgrade 3.6 Replica Set to 3.4</a></li><li class="toctree-l3"><a class="reference internal" href="3.6-downgrade-sharded-cluster.html">Downgrade 3.6 Sharded Cluster to 3.4</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="3.4.html">Release Notes for MongoDB 3.4</a><ul><li class="toctree-l3"><a class="reference internal" href="3.4-changelog.html">3.4 Changelog</a></li><li class="toctree-l3"><a class="reference internal" href="3.4-compatibility.html">Compatibility Changes in MongoDB 3.4</a></li><li class="toctree-l3"><a class="reference internal" href="3.4-upgrade-standalone.html">Upgrade a Standalone to 3.4</a></li><li class="toctree-l3"><a class="reference internal" href="3.4-upgrade-replica-set.html">Upgrade a Replica Set to 3.4</a></li><li class="toctree-l3"><a class="reference internal" href="3.4-upgrade-sharded-cluster.html">Upgrade a Sharded Cluster to 3.4</a></li><li class="toctree-l3"><a class="reference internal" href="3.4-downgrade.html">Downgrade MongoDB 3.4 to 3.2</a><ul><li class="toctree-l4"><a class="reference internal" href="3.4-downgrade-standalone.html">Downgrade 3.4 Standalone to 3.2</a></li><li class="toctree-l4"><a class="reference internal" href="3.4-downgrade-replica-set.html">Downgrade 3.4 Replica Set to 3.2</a></li><li class="toctree-l4"><a class="reference internal" href="3.4-downgrade-sharded-cluster.html">Downgrade 3.4 Sharded Cluster to 3.2</a></li></ul></li></ul></li><li class="toctree-l2"><a class="reference internal" href="3.2.html">Release Notes for MongoDB 3.2</a><ul><li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html">3.2 Changelog</a></li><li class="toctree-l3"><a class="reference internal" href="3.2-compatibility.html">Compatibility Changes in MongoDB 3.2</a><ul><li class="toctree-l4"><a class="reference internal" href="3.2-javascript.html">JavaScript Changes in MongoDB 3.2</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="3.2-upgrade.html">Upgrade MongoDB to 3.2</a></li><li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html">Downgrade MongoDB from 3.2</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="3.0.html">Release Notes for MongoDB 3.0</a><ul><li class="toctree-l3"><a class="reference internal" href="3.0-changelog.html">3.0 Changelog</a></li><li class="toctree-l3"><a class="reference internal" href="3.0-compatibility.html">Compatibility Changes in MongoDB 3.0</a></li><li class="toctree-l3"><a class="reference internal" href="3.0-upgrade.html">Upgrade MongoDB to 3.0</a></li><li class="toctree-l3"><a class="reference internal" href="3.0-scram.html">Upgrade to SCRAM</a></li><li class="toctree-l3"><a class="reference internal" href="3.0-downgrade.html">Downgrade MongoDB from 3.0</a></li></ul></li><li class="toctree-l2 current"><a class="reference internal current" href="">Release Notes for MongoDB 2.6</a><ul><li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html">2.6 Changelog</a></li><li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html">Compatibility Changes in MongoDB 2.6</a></li><li class="toctree-l3"><a class="reference internal" href="2.6-upgrade.html">Upgrade MongoDB to 2.6</a></li><li class="toctree-l3"><a class="reference internal" href="2.6-upgrade-authorization.html">Upgrade User Authorization Data to 2.6 Format</a></li><li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html">Downgrade MongoDB from 2.6</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="2.4.html">Release Notes for MongoDB 2.4</a><ul><li class="toctree-l3"><a class="reference internal" href="2.4-changelog.html">2.4 Changelog</a></li><li class="toctree-l3"><a class="reference internal" href="2.4-javascript.html">JavaScript Changes in MongoDB 2.4</a></li><li class="toctree-l3"><a class="reference internal" href="2.4-upgrade.html">Upgrade MongoDB to 2.4</a></li><li class="toctree-l3"><a class="reference internal" href="2.4-index-types.html">Compatibility and Index Type Changes in MongoDB 2.4</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="2.2.html">Release Notes for MongoDB 2.2</a></li><li class="toctree-l2"><a class="reference internal" href="2.0.html">Release Notes for MongoDB 2.0</a></li><li class="toctree-l2"><a class="reference internal" href="1.8.html">Release Notes for MongoDB 1.8</a></li><li class="toctree-l2"><a class="reference internal" 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                  <div class="section" id="release-notes-for-mongodb-2-6">
<h1>Release Notes for MongoDB 2.6<a class="headerlink" href="#release-notes-for-mongodb-2-6" title="Permalink to this headline">¶</a></h1>
<div class="contents twocols local topic" id="on-this-page">
<p class="topic-title first">On this page</p>
<ul class="simple">
<li><a class="reference internal" href="#minor-releases" id="id1">Minor Releases</a></li>
<li><a class="reference internal" href="#major-changes" id="id2">Major Changes</a></li>
<li><a class="reference internal" href="#security-improvements" id="id3">Security Improvements</a></li>
<li><a class="reference internal" href="#query-engine-improvements" id="id4">Query Engine Improvements</a></li>
<li><a class="reference internal" href="#improvements" id="id5">Improvements</a></li>
<li><a class="reference internal" href="#operational-changes" id="id6">Operational Changes</a></li>
<li><a class="reference internal" href="#mongodb-enterprise-features" id="id7">MongoDB Enterprise Features</a></li>
<li><a class="reference internal" href="#additional-information" id="id8">Additional Information</a></li>
</ul>
</div>
<p><em>April 8, 2014</em></p>
<p>MongoDB 2.6 is now available. Key features include aggregation
enhancements, text-search integration, query-engine improvements, a new
write-operation protocol, and security enhancements.</p>
<div class="section" id="minor-releases">
<h2>Minor Releases<a class="headerlink" href="#minor-releases" title="Permalink to this headline">¶</a></h2>
<div class="toctree-wrapper hidden compound">
<ul>
<li class="toctree-l1"><a class="reference internal" href="2.6-changelog.html">2.6 Changelog</a><ul>
<li class="toctree-l2"><a class="reference internal" href="2.6-changelog.html#id1">2.6.12 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#security">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#sharding">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#query">Query</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#write-operations">Write Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#storage">Storage</a><ul>
<li class="toctree-l4"><a class="reference internal" href="2.6-changelog.html#mmap">MMAP</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#operations">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#build-and-packaging">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#internals">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-changelog.html#changes">2.6.11 – Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#querying">Querying</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#replication">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id4">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#indexing">Indexing</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#networking">Networking</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#build-and-testing">Build and Testing</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-changelog.html#id5">2.6.10 – Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id7">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id8">Querying</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id9">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id10">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id11">Storage</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id12">Indexing</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#write-ops">Write Ops</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id13">Networking</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id14">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#shell">Shell</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#testing">Testing</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-changelog.html#id15">2.6.9 – Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id17">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id18">Querying</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#replication-and-sharding">Replication and Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id19">Storage</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#aggregation-framework">Aggregation Framework</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#build-and-platform">Build and Platform</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#diagnostics-and-internal-code">Diagnostics and Internal Code</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-changelog.html#id20">2.6.8 – Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#security-and-networking">Security and Networking</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#query-and-aggregation">Query and Aggregation</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id22">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id23">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id24">Storage</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#tools">Tools</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id25">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#usability">Usability</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id26">Testing</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-changelog.html#id27">2.6.7 – Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#stability">Stability</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id29">Querying</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id30">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id31">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#packaging">Packaging</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-changelog.html#id32">2.6.6 – Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id34">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id35">Stability</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id36">Querying</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id37">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id38">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id39">Storage</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#indexing-and-write-operations">Indexing and write Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#data-aggregation">Data Aggregation</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id40">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#logging-and-diagnostics">Logging and Diagnostics</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#testing-and-internals">Testing and Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-changelog.html#id41">2.6.5 – Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id43">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id44">Stability</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id45">Querying</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id46">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id47">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id48">Storage</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id49">Indexing</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id50">Write Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id51">Data Aggregation</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id52">Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id53">Logging and Diagnostics</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#internal-code-and-testing">Internal Code and Testing</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-changelog.html#id54">2.6.4 – Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id56">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id57">Querying</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id58">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id59">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id60">Storage</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id61">Indexing</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id62">Write Ops</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id63">Networking</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#geo">Geo</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#text-search">Text Search</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id64">Tools</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#admin">Admin</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id65">Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#javascript">JavaScript</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id66">Shell</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id67">Usability</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id68">Logging and Diagnostics</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id69">Testing</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-changelog.html#id70">2.6.3 – Changes</a></li>
<li class="toctree-l2"><a class="reference internal" href="2.6-changelog.html#id72">2.6.2 – Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id74">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id75">Querying</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#geospatial">Geospatial</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id76">Write Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id77">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id78">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#map-reduce">Map/Reduce</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id79">Storage</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id80">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#diagnostics">Diagnostics</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#administration">Administration</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id81">Tools</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id82">Shell</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#internal-code">Internal Code</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id83">Testing</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-changelog.html#id84">2.6.1 – Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id86">Stability</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id87">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id88">Querying</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id89">Geospatial</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id90">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id91">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id92">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html#id93">Write Operations</a></li>
</ul>
</li>
</ul>
</li>
</ul>
</div>
<div class="section" id="mar-24-2016">
<h3>2.6.12 – Mar 24, 2016<a class="headerlink" href="#mar-24-2016" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>Fixed issue with MMAPv1 journaling where the “last sequence number”
file (<code class="docutils literal"><span class="pre">lsn</span></code> file) may be ahead of what is synced to the data files:
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22261">SERVER-22261</a>.</li>
<li>Fixed issue that permitted the creation of new role with the same
name as a <a class="reference internal" href="../reference/built-in-roles.html"><span class="doc">built-in role</span></a>:
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-19284">SERVER-19284</a>.</li>
<li>Fixed issue where some index operations running during an active migration
may cause the migration operation to skip some documents:
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22535">SERVER-22535</a>.</li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.12%22%20AND%20project%20%3D%20SERVER">All issues closed in 2.6.12</a></li>
</ul>
</div>
<div class="section" id="aug-12-2015">
<h3>2.6.11 – Aug 12, 2015<a class="headerlink" href="#aug-12-2015" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>Improvements to query plan ranking <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-17815">SERVER-17815</a></li>
<li>Improved ability for <a class="reference internal" href="../reference/program/mongos.html#bin.mongos" title="bin.mongos"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongos</span></code></a> to detect replica set
failover and correctly route read operations to the new
primary <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-18280">SERVER-18280</a></li>
<li>Improved reporting of queries in <code class="docutils literal"><span class="pre">getMore</span></code> operation in
<a class="reference internal" href="../reference/method/db.currentOp.html#db.currentOp" title="db.currentOp()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.currentOp()</span></code></a> and the database
profiler <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-16265">SERVER-16265</a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.11%22%20AND%20project%20%3D%20SERVER">All issues closed in 2.6.11</a></li>
</ul>
</div>
<div class="section" id="may-19-2015">
<h3>2.6.10 – May 19, 2015<a class="headerlink" href="#may-19-2015" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>Improve user cache invalidation enforcement on <a class="reference internal" href="../reference/program/mongos.html#bin.mongos" title="bin.mongos"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongos</span></code></a>
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-11980">SERVER-11980</a></li>
<li>Provide correct rollbacks for collection creation
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-18211">SERVER-18211</a></li>
<li>Allow user inserts into the <code class="xref mongodb mongodb-data docutils literal"><span class="pre">system.profile</span></code> collection
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-18211">SERVER-18211</a></li>
<li>Fix to query system to ensure non-negation predicates get chosen
over negation predicates for multikey index bounds construction
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-18364">SERVER-18364</a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.10%22%20AND%20project%20%3D%20SERVER">All issues closed in 2.6.10</a></li>
</ul>
</div>
<div class="section" id="march-24-2015">
<h3>2.6.9 – March 24, 2015<a class="headerlink" href="#march-24-2015" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>Resolve connection handling related crash with <a class="reference internal" href="../reference/program/mongos.html#bin.mongos" title="bin.mongos"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongos</span></code></a>
instances <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-17441">SERVER-17441</a></li>
<li>Add server parameter to configure idle cursor timeout
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-8188">SERVER-8188</a></li>
<li>Remove duplicated (orphan) documents from aggregation pipelines with
<code class="docutils literal"><span class="pre">_id</span></code> queries in sharded clusters <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-17426">SERVER-17426</a></li>
<li>Fixed crash in <code class="docutils literal"><span class="pre">geoNear</span></code> command queries with multiple
<code class="docutils literal"><span class="pre">2dsphere</span></code> indexes <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-14723">SERVER-14723</a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.9%22%20AND%20project%20%3D%20SERVER">All issues closed in 2.6.9</a></li>
</ul>
</div>
<div class="section" id="february-25-2015">
<h3>2.6.8 – February 25, 2015<a class="headerlink" href="#february-25-2015" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>Add <a class="reference internal" href="../reference/command/listCollections.html#dbcmd.listCollections" title="listCollections"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">listCollections</span></code></a> command functionality to 2.6 shell
and client <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-17087">SERVER-17087</a></li>
<li><code class="docutils literal"><span class="pre">copydb</span></code>/<code class="docutils literal"><span class="pre">clone</span></code> commands can crash the
server if a primary steps down <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-16599">SERVER-16599</a></li>
<li>Secondary fasserts trying to replicate an index
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-16274">SERVER-16274</a></li>
<li>Query optimizer should always use equality predicate over unique
index when possible <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-15802">SERVER-15802</a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.8%22%20AND%20project%20%3D%20SERVER">All issues closed in 2.6.8</a></li>
</ul>
</div>
<div class="section" id="january-13-2015">
<h3>2.6.7 – January 13, 2015<a class="headerlink" href="#january-13-2015" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>Decreased <a class="reference internal" href="../reference/program/mongos.html#bin.mongos" title="bin.mongos"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongos</span></code></a> memory footprint when shards have several
tags <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-16683">SERVER-16683</a></li>
<li>Removed check for shard version if the primary server is down
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-16237">SERVER-16237</a></li>
<li>Fixed: <code class="docutils literal"><span class="pre">/etc/init.d/mongod</span></code> startup script failure with dirname message
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-16081">SERVER-16081</a></li>
<li>Fixed: <a class="reference internal" href="../reference/program/mongos.html#bin.mongos" title="bin.mongos"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongos</span></code></a> can cause shards to hit the in-memory sort limit
by requesting more results than needed <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-14306">SERVER-14306</a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.7%22%20AND%20project%20%3D%20SERVER">All issues closed in 2.6.7</a></li>
</ul>
</div>
<div class="section" id="december-09-2014">
<h3>2.6.6 – December 09, 2014<a class="headerlink" href="#december-09-2014" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>Fixed: Evaluating candidate query plans with concurrent writes on same
collection may crash <a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a> <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-15580">SERVER-15580</a></li>
<li>Fixed: 2.6 <a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a> crashes with segfault when added to a 2.8 replica set
with 12 or more members <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-16107">SERVER-16107</a></li>
<li>Fixed: <a class="reference internal" href="../reference/operator/query/regex.html#op._S_regex" title="$regex"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$regex</span></code></a>, <a class="reference internal" href="../reference/operator/query/in.html#op._S_in" title="$in"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$in</span></code></a> and <code class="xref mongodb mongodb-query docutils literal"><span class="pre">$sort</span></code> with index returns too
many results <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-15696">SERVER-15696</a></li>
<li>Change: <a class="reference internal" href="../reference/command/moveChunk.html#dbcmd.moveChunk" title="moveChunk"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">moveChunk</span></code></a> will fail if there is data on the target
shard and a required index does not exist.
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-12472">SERVER-12472</a></li>
<li>Primary should abort if encountered problems writing to the oplog
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-12058">SERVER-12058</a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.6%22%20AND%20project%20%3D%20SERVER">All issues closed in 2.6.6</a></li>
</ul>
</div>
<div class="section" id="october-07-2014">
<h3>2.6.5 – October 07, 2014<a class="headerlink" href="#october-07-2014" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$rename</span></code> now uses correct dotted source paths <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-15029">SERVER-15029</a></li>
<li>Partially written journal last section does not affect recovery
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-15111">SERVER-15111</a></li>
<li>Explicitly zero <code class="docutils literal"><span class="pre">.ns</span></code> files on creation <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-15369">SERVER-15369</a></li>
<li>Plan ranker will no longer favor intersection plans if predicate generates empty range
index scan <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-14961">SERVER-14961</a></li>
<li>Generate Community and Enterprise packages for SUSE 11
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-10642">SERVER-10642</a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.5%22%20AND%20project%20%3D%20SERVER">All issues closed in 2.6.5</a></li>
</ul>
</div>
<div class="section" id="august-11-2014">
<h3>2.6.4 – August 11, 2014<a class="headerlink" href="#august-11-2014" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>Fix for <code class="docutils literal"><span class="pre">text</span></code> index where under specific circumstances, in-place
updates to a <code class="docutils literal"><span class="pre">text</span></code>-indexed field may result in
incorrect/incomplete results <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-14738">SERVER-14738</a></li>
<li>Check the size of the split point before performing a manual split
chunk operation <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-14431">SERVER-14431</a></li>
<li>Ensure read preferences are re-evaluated by drawing secondary
connections from a global pool and releasing back to the pool at the
end of a query/command <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-9788">SERVER-9788</a></li>
<li>Allow read from secondaries when both audit and authorization are
enabled in a sharded cluster <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-14170">SERVER-14170</a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.4%22%20AND%20project%20%3D%20SERVER">All issues closed in 2.6.4</a></li>
</ul>
</div>
<div class="section" id="june-19-2014">
<h3>2.6.3 – June 19, 2014<a class="headerlink" href="#june-19-2014" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>Equality queries on <code class="docutils literal"><span class="pre">_id</span></code> with projection may return no results
on sharded collections <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-14302">SERVER-14302</a>.</li>
<li>Equality queries on <code class="docutils literal"><span class="pre">_id</span></code> with projection on <code class="docutils literal"><span class="pre">_id</span></code> may return
orphan documents on sharded collections <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-14304">SERVER-14304</a>.</li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.3%22%20AND%20project%20%3D%20SERVER">All issues closed in 2.6.3</a>.</li>
</ul>
</div>
<div class="section" id="june-16-2014">
<h3>2.6.2 – June 16, 2014<a class="headerlink" href="#june-16-2014" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>Query plans with differing performance can tie during plan ranking
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-13675">SERVER-13675</a>.</li>
<li><a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a> may terminate if x.509 authentication certificate is invalid
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-13753">SERVER-13753</a>.</li>
<li>Temporary map/reduce collections are incorrectly replicated to secondaries
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-13981">SERVER-13981</a>.</li>
<li><a class="reference internal" href="../reference/program/mongos.html#bin.mongos" title="bin.mongos"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongos</span></code></a> incorrectly targets multiple shards for nested
field shard key predicates <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-14138">SERVER-14138</a>.</li>
<li><a class="reference internal" href="../reference/method/rs.stepDown.html#rs.stepDown" title="rs.stepDown()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">rs.stepDown()</span></code></a> during mapReduce causes <code class="docutils literal"><span class="pre">fassert</span></code> when
writing to op log <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-14186">SERVER-14186</a>.</li>
</ul>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.2%22%20AND%20project%20%3D%20SERVER">All issues closed in 2.6.2</a>.</li>
</ul>
</div>
<div class="section" id="may-5-2014">
<h3>2.6.1 – May 5, 2014<a class="headerlink" href="#may-5-2014" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>Fix to install MongoDB service on Windows with the <code class="docutils literal"><span class="pre">--install</span></code>
option <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-13515">SERVER-13515</a>.</li>
<li>Allow direct upgrade from 2.4.x to 2.6.0 via <code class="docutils literal"><span class="pre">yum</span></code>
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-13563">SERVER-13563</a>.</li>
<li>Fix issues with background index builds on secondaries:
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-13589">SERVER-13589</a> and <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-13620">SERVER-13620</a>.</li>
<li>Redact credential information passed as startup options
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-13644">SERVER-13644</a>.</li>
<li><a class="reference internal" href="2.6-changelog.html#id84"><span class="std std-ref">2.6.1 Changelog</span></a>.</li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.1%22%20AND%20project%20%3D%20SERVER">All issues closed in 2.6.1</a>.</li>
</ul>
</div>
</div>
<div class="section" id="major-changes">
<h2>Major Changes<a class="headerlink" href="#major-changes" title="Permalink to this headline">¶</a></h2>
<p>The following changes in MongoDB affect both the standard and Enterprise
editions:</p>
<div class="section" id="aggregation-enhancements">
<span id="rn-2-6-aggregation-cursor"></span><h3>Aggregation Enhancements<a class="headerlink" href="#aggregation-enhancements" title="Permalink to this headline">¶</a></h3>
<p>The aggregation pipeline adds the ability to return result sets of any
size, either by returning a cursor or writing the output to
a collection. Additionally, the aggregation pipeline supports
variables and adds new operations to handle sets and redact data.</p>
<ul class="simple">
<li>The <a class="reference internal" href="../reference/method/db.collection.aggregate.html#db.collection.aggregate" title="db.collection.aggregate()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.aggregate()</span></code></a> now returns a cursor, which
enables the aggregation pipeline to return result sets of any size.</li>
<li>Aggregation pipelines now support an <code class="docutils literal"><span class="pre">explain</span></code> operation to aid
analysis of aggregation operations.</li>
<li>Aggregation can now use a more efficient external-disk-based sorting
process.</li>
<li>New pipeline stages:<ul>
<li><a class="reference internal" href="../reference/operator/aggregation/out.html#pipe._S_out" title="$out"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$out</span></code></a> stage to output to a collection.</li>
<li><a class="reference internal" href="../reference/operator/aggregation/redact.html#pipe._S_redact" title="$redact"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$redact</span></code></a> stage to allow additional control to accessing
the data.</li>
</ul>
</li>
<li>New or modified operators:<ul>
<li><a class="reference internal" href="../meta/aggregation-quick-reference.html#agg-qr-set-operators"><span class="std std-ref">set expression operators</span></a>.</li>
<li><a class="reference internal" href="../reference/operator/aggregation/let.html#exp._S_let" title="$let"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$let</span></code></a> and <a class="reference internal" href="../reference/operator/aggregation/map.html#exp._S_map" title="$map"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$map</span></code></a> operators to allow for
the use of variables.</li>
<li><a class="reference internal" href="../reference/operator/aggregation/literal.html#exp._S_literal" title="$literal"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$literal</span></code></a> operator and <a class="reference internal" href="../reference/operator/aggregation/size.html#exp._S_size" title="$size"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$size</span></code></a> operator.</li>
<li><a class="reference internal" href="../reference/operator/aggregation/cond.html#exp._S_cond" title="$cond"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$cond</span></code></a> expression now accepts either an object or
an array.</li>
</ul>
</li>
</ul>
</div>
<div class="section" id="text-search-integration">
<span id="rel-notes-text-query-operator"></span><h3>Text Search Integration<a class="headerlink" href="#text-search-integration" title="Permalink to this headline">¶</a></h3>
<p>Text search is now enabled by default, and the query system, including
the aggregation pipeline <a class="reference internal" href="../reference/operator/aggregation/match.html#pipe._S_match" title="$match"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$match</span></code></a> stage, includes the
<a class="reference internal" href="../reference/operator/query/text.html#op._S_text" title="$text"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$text</span></code></a> operator, which resolves text-search queries.</p>
<p>MongoDB 2.6 includes an updated <a class="reference internal" href="../core/index-text.html"><span class="doc">text index</span></a> format and deprecates the <code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">text</span></code>
command.</p>
</div>
<div class="section" id="insert-and-update-improvements">
<span id="rel-notes-data-modification"></span><h3>Insert and Update Improvements<a class="headerlink" href="#insert-and-update-improvements" title="Permalink to this headline">¶</a></h3>
<p>Improvements to the update and insert systems include additional
operations and improvements that increase consistency of modified
data.</p>
<ul class="simple">
<li>MongoDB preserves the order of the document fields following write
operations <em>except</em> for the following cases:<ul>
<li>The <code class="docutils literal"><span class="pre">_id</span></code> field is always the first field in the document.</li>
<li>Updates that include <a class="reference internal" href="../reference/operator/update/rename.html#up._S_rename" title="$rename"><code class="xref mongodb mongodb-update docutils literal"><span class="pre">renaming</span></code></a> of field names may
result in the reordering of fields in the document.</li>
</ul>
</li>
<li>New or enhanced update operators:<ul>
<li><a class="reference internal" href="../reference/operator/update/bit.html#up._S_bit" title="$bit"><code class="xref mongodb mongodb-update docutils literal"><span class="pre">$bit</span></code></a> operator supports bitwise <code class="docutils literal"><span class="pre">xor</span></code> operation.</li>
<li><a class="reference internal" href="../reference/operator/update/min.html#up._S_min" title="$min"><code class="xref mongodb mongodb-update docutils literal"><span class="pre">$min</span></code></a> and <a class="reference internal" href="../reference/operator/update/max.html#up._S_max" title="$max"><code class="xref mongodb mongodb-update docutils literal"><span class="pre">$max</span></code></a> operators that perform
conditional update depending on the relative size of the specified
value and the current value of a field.</li>
<li><a class="reference internal" href="../reference/operator/update/push.html#up._S_push" title="$push"><code class="xref mongodb mongodb-update docutils literal"><span class="pre">$push</span></code></a> operator has enhanced support for the
<a class="reference internal" href="../reference/operator/update/sort.html#up._S_sort" title="$sort"><code class="xref mongodb mongodb-update docutils literal"><span class="pre">$sort</span></code></a>, <a class="reference internal" href="../reference/operator/update/slice.html#up._S_slice" title="$slice"><code class="xref mongodb mongodb-update docutils literal"><span class="pre">$slice</span></code></a>, and <a class="reference internal" href="../reference/operator/update/each.html#up._S_each" title="$each"><code class="xref mongodb mongodb-update docutils literal"><span class="pre">$each</span></code></a> modifiers
and supports a new <a class="reference internal" href="../reference/operator/update/position.html#up._S_position" title="$position"><code class="xref mongodb mongodb-update docutils literal"><span class="pre">$position</span></code></a> modifier.</li>
<li><a class="reference internal" href="../reference/operator/update/currentDate.html#up._S_currentDate" title="$currentDate"><code class="xref mongodb mongodb-update docutils literal"><span class="pre">$currentDate</span></code></a> operator to set the value of a field to the
current date.</li>
</ul>
</li>
<li>The <a class="reference internal" href="../reference/operator/update/mul.html#up._S_mul" title="$mul"><code class="xref mongodb mongodb-update docutils literal"><span class="pre">$mul</span></code></a> operator for multiplicative increments for insert
and update operations.</li>
</ul>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="2.6-compatibility.html#update-operations-incompatibility"><span class="std std-ref">Update Operator Syntax Validation</span></a></p>
</div>
</div>
<div class="section" id="new-write-operation-protocol">
<span id="rel-notes-write-operations"></span><h3>New Write Operation Protocol<a class="headerlink" href="#new-write-operation-protocol" title="Permalink to this headline">¶</a></h3>
<p>A new write protocol integrates write operations with
write concerns. The protocol also provides improved
support for bulk operations.</p>
<p>MongoDB 2.6 adds the write commands <a class="reference internal" href="../reference/command/insert.html#dbcmd.insert" title="insert"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">insert</span></code></a>,
<a class="reference internal" href="../reference/command/update.html#dbcmd.update" title="update"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">update</span></code></a>, and <a class="reference internal" href="../reference/command/delete.html#dbcmd.delete" title="delete"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">delete</span></code></a>, which provide the basis
for the improved bulk insert. All officially supported MongoDB drivers
support the new write commands.</p>
<p>The <a class="reference internal" href="../reference/program/mongo.html#bin.mongo" title="bin.mongo"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongo</span></code></a> shell now includes
methods to perform bulk-write operations. See <a class="reference internal" href="../reference/method/Bulk.html#Bulk" title="Bulk()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">Bulk()</span></code></a> for
more information.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="2.6-compatibility.html#write-methods-incompatibility"><span class="std std-ref">Write Method Acknowledgements</span></a></p>
</div>
</div>
<div class="section" id="msi-package-for-mongodb-available-for-windows">
<h3>MSI Package for MongoDB Available for Windows<a class="headerlink" href="#msi-package-for-mongodb-available-for-windows" title="Permalink to this headline">¶</a></h3>
<p>MongoDB now distributes MSI packages for Microsoft Windows. This is the
recommended method for MongoDB installation under Windows.</p>
</div>
</div>
<div class="section" id="security-improvements">
<span id="relnotes-security"></span><h2>Security Improvements<a class="headerlink" href="#security-improvements" title="Permalink to this headline">¶</a></h2>
<p>MongoDB 2.6 enhances support for secure deployments through improved SSL
support, x.509-based authentication, an improved authorization system
with more granular controls, as well as centralized credential storage, and
improved user management tools.</p>
<p>Specifically these changes include:</p>
<ul class="simple">
<li>A new <a class="reference internal" href="../core/authorization.html#authorization"><span class="std std-ref">authorization model</span></a> that provides the
ability to create custom <a class="reference internal" href="../core/security-user-defined-roles.html#user-defined-roles"><span class="std std-ref">User-Defined Roles</span></a> and the ability to
specify user privileges at a collection-level granularity.</li>
<li>Global user management, which stores all user and
user-defined role data in the <code class="docutils literal"><span class="pre">admin</span></code> database and provides a new
set of commands for managing users and roles.</li>
<li>x.509 certificate authentication for <a class="reference internal" href="../tutorial/configure-x509-client-authentication.html"><span class="doc">client authentication</span></a> as well as for
<a class="reference internal" href="../tutorial/configure-x509-member-authentication.html"><span class="doc">internal authentication</span></a> of sharded cluster and/or
replica set  members. x.509 authentication is only available
for deployments using SSL.</li>
<li>Enhanced SSL Support:<ul>
<li><a class="reference internal" href="../tutorial/upgrade-cluster-to-ssl.html"><span class="doc">Rolling upgrades of clusters</span></a> to use SSL.</li>
<li><a class="reference internal" href="../tutorial/configure-ssl-clients.html#mongodb-tools-support-ssl"><span class="std std-ref">MongoDB Tools</span></a> support connections to
<a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a> and <a class="reference internal" href="../reference/program/mongos.html#bin.mongos" title="bin.mongos"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongos</span></code></a> instances using SSL
connections.</li>
<li><a class="reference internal" href="../tutorial/configure-ssl.html#ssl-certificate-password"><span class="std std-ref">Prompt for passphrase</span></a>
by <a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a> or <a class="reference internal" href="../reference/program/mongos.html#bin.mongos" title="bin.mongos"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongos</span></code></a> at startup.</li>
<li>Require the use of strong SSL ciphers, with a minimum 128-bit key
length for all connections. The strong-cipher requirement prevents
an old or malicious client from forcing use of a weak cipher.</li>
</ul>
</li>
<li>MongoDB disables the http interface by default, limiting
<a class="reference internal" href="../core/security-hardening.html"><span class="doc">network exposure</span></a>. To enable the
interface, see <code class="xref mongodb mongodb-setting docutils literal"><span class="pre">enabled</span></code>.</li>
</ul>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="2.6-compatibility.html#authentication-incompatibility"><span class="std std-ref">New Authorization Model</span></a>,
<a class="reference internal" href="2.6-compatibility.html#ssl-hostname-validation"><span class="std std-ref">SSL Certificate Hostname Validation</span></a>,
and <a class="reference internal" href="../administration/security-checklist.html"><span class="doc">Security Checklist</span></a>.</p>
</div>
</div>
<div class="section" id="query-engine-improvements">
<h2>Query Engine Improvements<a class="headerlink" href="#query-engine-improvements" title="Permalink to this headline">¶</a></h2>
<ul class="simple">
<li>MongoDB can now use <a class="reference internal" href="../core/index-intersection.html"><span class="doc">index intersection</span></a> to fulfill queries supported by more
than one index.</li>
<li><a class="reference internal" href="../core/query-plans.html#index-filters"><span class="std std-ref">Index Filters</span></a> to limit which indexes can become the winning
plan for a query.</li>
<li><a class="reference internal" href="../reference/method/js-plan-cache.html"><span class="doc">Query Plan Cache Methods</span></a> methods to view and clear the
<a class="reference internal" href="../core/query-plans.html"><span class="doc">query plans</span></a> cached by the query optimizer.</li>
<li>MongoDB can now use <a class="reference internal" href="../reference/method/cursor.count.html#cursor.count" title="cursor.count()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">count()</span></code></a> with
<a class="reference internal" href="../reference/method/cursor.hint.html#cursor.hint" title="cursor.hint()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">hint()</span></code></a>. See <a class="reference internal" href="../reference/method/cursor.count.html#cursor.count" title="cursor.count()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">count()</span></code></a> for details.</li>
</ul>
</div>
<div class="section" id="improvements">
<h2>Improvements<a class="headerlink" href="#improvements" title="Permalink to this headline">¶</a></h2>
<div class="section" id="geospatial-enhancements">
<h3>Geospatial Enhancements<a class="headerlink" href="#geospatial-enhancements" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li><a class="reference internal" href="../core/2dsphere.html#dsphere-v2"><span class="std std-ref">2dsphere indexes version 2</span></a>.</li>
<li>Support for <a class="reference internal" href="../reference/geojson.html#geojson-multipoint"><span class="std std-ref">MultiPoint</span></a>,
<a class="reference internal" href="../reference/geojson.html#geojson-multilinestring"><span class="std std-ref">MultiLineString</span></a>, <a class="reference internal" href="../reference/geojson.html#geojson-multipolygon"><span class="std std-ref">MultiPolygon</span></a>, and
<a class="reference internal" href="../reference/geojson.html#geojson-geometrycollection"><span class="std std-ref">GeometryCollection</span></a>.</li>
<li>Support for geospatial query clauses in <a class="reference internal" href="../reference/operator/query/or.html#op._S_or" title="$or"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$or</span></code></a> expressions.</li>
</ul>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="2.6-compatibility.html#dsphere-version-incompatibility"><span class="std std-ref">2dsphere Index Version 2</span></a>,
<a class="reference internal" href="2.6-compatibility.html#geo-maxdistance-incompatibility"><span class="std std-ref">$maxDistance Changes</span></a>,
<a class="reference internal" href="2.6-compatibility.html#uniquedocs-incompatibility"><span class="std std-ref">Deprecated $uniqueDocs</span></a>,
<a class="reference internal" href="2.6-compatibility.html#geospatial-validation-incompatibility"><span class="std std-ref">Stronger Validation of Geospatial Queries</span></a></p>
</div>
</div>
<div class="section" id="index-build-enhancements">
<h3>Index Build Enhancements<a class="headerlink" href="#index-build-enhancements" title="Permalink to this headline">¶</a></h3>
<ul>
<li><p class="first"><a class="reference internal" href="../core/index-creation.html#index-creation-background"><span class="std std-ref">Background index build</span></a> allowed on
secondaries. If you initiate a background index build on a
<a class="reference internal" href="../reference/glossary.html#term-primary"><span class="xref std std-term">primary</span></a>, the secondaries will replicate the index build in
the background.</p>
</li>
<li><p class="first">Automatic rebuild of interrupted index builds after a restart.</p>
<ul class="simple">
<li>If a standalone or a primary instance terminates during an index
build <em>without a clean shutdown</em>, <a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a> now restarts
the index build when the instance restarts. If the instance shuts
down cleanly or if a user kills the index build, the interrupted
index builds do not automatically restart upon the restart of the
server.</li>
<li>If a secondary instance terminates during an index build, the
<a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a> instance will now restart the interrupted index
build when the instance restarts.</li>
</ul>
<p>To disable this behavior, use the <a class="reference internal" href="../reference/program/mongod.html#cmdoption-mongod-noindexbuildretry"><code class="xref std std-option docutils literal"><span class="pre">--noIndexBuildRetry</span></code></a>
command-line option.</p>
</li>
<li><p class="first"><a class="reference internal" href="../reference/method/db.collection.ensureIndex.html#db.collection.ensureIndex" title="db.collection.ensureIndex()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">ensureIndex()</span></code></a> now wraps a new
<code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">createIndex</span></code> command.</p>
</li>
<li><p class="first">The <code class="docutils literal"><span class="pre">dropDups</span></code> option to <a class="reference internal" href="../reference/method/db.collection.ensureIndex.html#db.collection.ensureIndex" title="db.collection.ensureIndex()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">ensureIndex()</span></code></a>
and <code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">createIndex</span></code> is deprecated.</p>
</li>
</ul>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="2.6-compatibility.html#index-key-length-incompatibility"><span class="std std-ref">Enforce Index Key Length Limit</span></a></p>
</div>
</div>
<div class="section" id="enhanced-sharding-and-replication-administration">
<h3>Enhanced Sharding and Replication Administration<a class="headerlink" href="#enhanced-sharding-and-replication-administration" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>New <a class="reference internal" href="../reference/command/cleanupOrphaned.html#dbcmd.cleanupOrphaned" title="cleanupOrphaned"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">cleanupOrphaned</span></code></a> command to remove <a class="reference internal" href="../reference/glossary.html#term-orphaned-document"><span class="xref std std-term">orphaned
documents</span></a> from a shard.</li>
<li>New <a class="reference internal" href="../reference/command/mergeChunks.html#dbcmd.mergeChunks" title="mergeChunks"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">mergeChunks</span></code></a> command to combine contiguous chunks
located on a single shard. See <a class="reference internal" href="../reference/command/mergeChunks.html#dbcmd.mergeChunks" title="mergeChunks"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">mergeChunks</span></code></a> and
<a class="reference internal" href="../tutorial/merge-chunks-in-sharded-cluster.html"><span class="doc">Merge Chunks in a Sharded Cluster</span></a>.</li>
<li>New <a class="reference internal" href="../reference/method/rs.printReplicationInfo.html#rs.printReplicationInfo" title="rs.printReplicationInfo()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">rs.printReplicationInfo()</span></code></a> and
<a class="reference internal" href="../reference/method/rs.printSlaveReplicationInfo.html#rs.printSlaveReplicationInfo" title="rs.printSlaveReplicationInfo()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">rs.printSlaveReplicationInfo()</span></code></a> methods to provide a
formatted report of the status of a replica set from the perspective
of the primary and the secondary, respectively.</li>
</ul>
</div>
<div class="section" id="configuration-options-yaml-file-format">
<h3>Configuration Options YAML File Format<a class="headerlink" href="#configuration-options-yaml-file-format" title="Permalink to this headline">¶</a></h3>
<p>MongoDB 2.6 supports a YAML-based configuration file format in addition
to the previous configuration file format. See the documentation of
the <a class="reference internal" href="../reference/configuration-options.html"><span class="doc">Configuration File</span></a> for
more information.</p>
</div>
</div>
<div class="section" id="operational-changes">
<h2>Operational Changes<a class="headerlink" href="#operational-changes" title="Permalink to this headline">¶</a></h2>
<div class="section" id="storage">
<h3>Storage<a class="headerlink" href="#storage" title="Permalink to this headline">¶</a></h3>
<p><code class="xref mongodb mongodb-collflag docutils literal"><span class="pre">usePowerOf2Sizes</span></code> is now the default allocation strategy for
all new collections. The new allocation strategy uses more storage
relative to total document size but results in lower levels of
storage fragmentation and more predictable storage capacity planning
over time.</p>
<p>To use the previous <em>exact-fit allocation strategy</em>:</p>
<ul>
<li><p class="first">For a specific collection, use <a class="reference internal" href="../reference/command/collMod.html#dbcmd.collMod" title="collMod"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">collMod</span></code></a> with
<code class="xref mongodb mongodb-collflag docutils literal"><span class="pre">usePowerOf2Sizes</span></code> set to <code class="docutils literal"><span class="pre">false</span></code>.</p>
</li>
<li><p class="first">For all new collections on an entire <a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a> instance,
set <code class="xref mongodb mongodb-parameter docutils literal"><span class="pre">newCollectionsUsePowerOf2Sizes</span></code> to <code class="docutils literal"><span class="pre">false</span></code>.</p>
<p>New collections include those: created during
<a class="reference internal" href="../core/replica-set-sync.html#replica-set-initial-sync"><span class="std std-ref">initial sync</span></a>, as well as those
created by the <a class="reference internal" href="../reference/program/mongorestore.html#bin.mongorestore" title="bin.mongorestore"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongorestore</span></code></a> and <a class="reference internal" href="../reference/program/mongoimport.html#bin.mongoimport" title="bin.mongoimport"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongoimport</span></code></a>
tools, by running <a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a> with the <a class="reference internal" href="../reference/program/mongod.html#cmdoption-mongod-repair"><code class="xref std std-option docutils literal"><span class="pre">--repair</span></code></a> option, as well as the
<code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">restoreDatabase</span></code> command.</p>
</li>
</ul>
<p>See <a class="reference external" href="https://docs.mongodb.com/v2.6/core/storage">/core/storage</a> for more information about MongoDB’s storage system.</p>
</div>
<div class="section" id="networking">
<h3>Networking<a class="headerlink" href="#networking" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>Removed upward limit for the <a class="reference internal" href="../reference/configuration-options.html#net.maxIncomingConnections" title="net.maxIncomingConnections"><code class="xref mongodb mongodb-setting docutils literal"><span class="pre">maxIncomingConnections</span></code></a> for <a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a>
and <a class="reference internal" href="../reference/program/mongos.html#bin.mongos" title="bin.mongos"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongos</span></code></a>. Previous versions capped the maximum possible
<a class="reference internal" href="../reference/configuration-options.html#net.maxIncomingConnections" title="net.maxIncomingConnections"><code class="xref mongodb mongodb-setting docutils literal"><span class="pre">maxIncomingConnections</span></code></a> setting at <code class="docutils literal"><span class="pre">20,000</span></code> connections.</li>
<li>Connection pools for a <a class="reference internal" href="../reference/program/mongos.html#bin.mongos" title="bin.mongos"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongos</span></code></a> instance may be used by multiple
MongoDB servers. This can reduce the number of connections needed
for high-volume workloads and reduce resource consumption in
sharded clusters.</li>
<li>The C++ driver now monitors <a class="reference internal" href="../reference/glossary.html#term-replica-set"><span class="xref std std-term">replica set</span></a> health with the
<a class="reference internal" href="../reference/command/isMaster.html#dbcmd.isMaster" title="isMaster"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">isMaster</span></code></a> command instead of
<a class="reference internal" href="../reference/command/replSetGetStatus.html#dbcmd.replSetGetStatus" title="replSetGetStatus"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">replSetGetStatus</span></code></a>. This allows the C++ driver to support
systems that require authentication.</li>
<li>New <a class="reference internal" href="../reference/method/cursor.maxTimeMS.html#cursor.maxTimeMS" title="cursor.maxTimeMS()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">cursor.maxTimeMS()</span></code></a> and corresponding <code class="docutils literal"><span class="pre">maxTimeMS</span></code>
option for commands to specify a time limit.</li>
</ul>
</div>
<div class="section" id="tool-improvements">
<h3>Tool Improvements<a class="headerlink" href="#tool-improvements" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li><a class="reference internal" href="../reference/program/mongo.html#bin.mongo" title="bin.mongo"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongo</span></code></a> shell supports a global <a class="reference internal" href="../reference/program/mongo.html#mongo-global-mongorc-file"><span class="std std-ref">/etc/mongorc.js</span></a>.</li>
<li>All MongoDB <a class="reference internal" href="../reference/program.html"><span class="doc">executable files</span></a> now support
the <code class="docutils literal"><span class="pre">--quiet</span></code> option to suppress all logging output except for
error messages.</li>
<li><a class="reference internal" href="../reference/program/mongoimport.html#bin.mongoimport" title="bin.mongoimport"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongoimport</span></code></a> uses the input filename, without the file
extension if any, as the collection name if run without the <code class="docutils literal"><span class="pre">-c</span></code> or
<code class="docutils literal"><span class="pre">--collection</span></code> specification.</li>
<li><a class="reference internal" href="../reference/program/mongoexport.html#bin.mongoexport" title="bin.mongoexport"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongoexport</span></code></a> can now constrain export data using
<a class="reference internal" href="../reference/program/mongoexport.html#cmdoption-mongoexport-skip"><code class="xref std std-option docutils literal"><span class="pre">--skip</span></code></a> and <a class="reference internal" href="../reference/program/mongoexport.html#cmdoption-mongoexport-limit"><code class="xref std std-option docutils literal"><span class="pre">--limit</span></code></a>, as well as order the documents
in an export using the <a class="reference internal" href="../reference/program/mongoexport.html#cmdoption-mongoexport-sort"><code class="xref std std-option docutils literal"><span class="pre">--sort</span></code></a> option.</li>
<li><a class="reference internal" href="../reference/program/mongostat.html#bin.mongostat" title="bin.mongostat"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongostat</span></code></a> can support the use of <a class="reference internal" href="../reference/program/mongostat.html#cmdoption-mongostat-rowcount"><code class="xref std std-option docutils literal"><span class="pre">--rowcount</span></code></a>
(<a class="reference internal" href="../reference/program/mongostat.html#cmdoption-mongostat-rowcount"><code class="xref std std-option docutils literal"><span class="pre">-n</span></code></a>) with the <a class="reference internal" href="../reference/program/mongostat.html#cmdoption-mongostat-discover"><code class="xref std std-option docutils literal"><span class="pre">--discover</span></code></a> option to produce the
specified number of output lines.</li>
<li>Add strict mode representation for <a class="reference internal" href="../reference/mongodb-extended-json-v1.html#bson.data_numberlong" title="data_numberlong"><code class="xref mongodb mongodb-bsontype docutils literal"><span class="pre">data_numberlong</span></code></a> for
use by <a class="reference internal" href="../reference/program/mongoexport.html#bin.mongoexport" title="bin.mongoexport"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongoexport</span></code></a> and <a class="reference internal" href="../reference/program/mongoimport.html#bin.mongoimport" title="bin.mongoimport"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongoimport</span></code></a>.</li>
</ul>
</div>
</div>
<div class="section" id="mongodb-enterprise-features">
<h2>MongoDB Enterprise Features<a class="headerlink" href="#mongodb-enterprise-features" title="Permalink to this headline">¶</a></h2>
<p>The following changes are specific to MongoDB Enterprise Editions:</p>
<div class="section" id="mongodb-enterprise-for-windows">
<h3>MongoDB Enterprise for Windows<a class="headerlink" href="#mongodb-enterprise-for-windows" title="Permalink to this headline">¶</a></h3>
<p><a class="reference internal" href="../tutorial/install-mongodb-enterprise-on-windows.html"><span class="doc">MongoDB Enterprise for Windows</span></a> is now available. It
includes support for Kerberos, SSL, and SNMP.</p>
<p>MongoDB Enterprise for Windows does <strong>not</strong> include LDAP support for
authentication. However, MongoDB Enterprise for Linux supports using
LDAP authentication with an ActiveDirectory server.</p>
<p>MongoDB Enterprise for Windows includes OpenSSL version 1.0.1g.</p>
</div>
<div class="section" id="auditing">
<h3>Auditing<a class="headerlink" href="#auditing" title="Permalink to this headline">¶</a></h3>
<p>MongoDB Enterprise adds <a class="reference internal" href="../core/auditing.html"><span class="doc">auditing</span></a> capability for
<a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a> and <a class="reference internal" href="../reference/program/mongos.html#bin.mongos" title="bin.mongos"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongos</span></code></a> instances. See <a class="reference internal" href="../core/auditing.html#auditing"><span class="std std-ref">Auditing</span></a>
for details.</p>
</div>
<div class="section" id="ldap-support-for-authentication">
<span id="relnotes-ldap-authentication"></span><h3>LDAP Support for Authentication<a class="headerlink" href="#ldap-support-for-authentication" title="Permalink to this headline">¶</a></h3>
<p>MongoDB Enterprise provides support for proxy authentication of users.
This allows administrators to configure a MongoDB cluster to
authenticate users by proxying authentication requests to a specified
Lightweight Directory Access Protocol (LDAP) service. See
<a class="reference internal" href="../tutorial/configure-ldap-sasl-openldap.html"><span class="doc">Authenticate Using SASL and LDAP with OpenLDAP</span></a> and
<a class="reference internal" href="../tutorial/configure-ldap-sasl-activedirectory.html"><span class="doc">Authenticate Using SASL and LDAP with ActiveDirectory</span></a> for details.</p>
<p>MongoDB Enterprise for Windows does <strong>not</strong> include LDAP support for
authentication. However, MongoDB Enterprise for Linux supports using
LDAP authentication with an ActiveDirectory server.</p>
<p>MongoDB does <strong>not</strong> support LDAP authentication in mixed sharded
cluster deployments that contain both version 2.4 and version 2.6
shards. See <a class="reference internal" href="2.6-upgrade.html"><span class="doc">Upgrade MongoDB to 2.6</span></a> for upgrade instructions.</p>
</div>
<div class="section" id="expanded-snmp-support">
<h3>Expanded SNMP Support<a class="headerlink" href="#expanded-snmp-support" title="Permalink to this headline">¶</a></h3>
<p>MongoDB Enterprise has greatly expanded its SNMP support to provide
SNMP access to nearly the full range of metrics provided by
<a class="reference internal" href="../reference/method/db.serverStatus.html#db.serverStatus" title="db.serverStatus()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.serverStatus()</span></code></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="2.6-compatibility.html#snmp-iana-mib-incompatibility"><span class="std std-ref">SNMP Changes</span></a></p>
</div>
</div>
</div>
<div class="section" id="additional-information">
<h2>Additional Information<a class="headerlink" href="#additional-information" title="Permalink to this headline">¶</a></h2>
<div class="section" id="changes-affecting-compatibility">
<h3>Changes Affecting Compatibility<a class="headerlink" href="#changes-affecting-compatibility" title="Permalink to this headline">¶</a></h3>
<div class="toctree-wrapper hidden compound">
<ul>
<li class="toctree-l1"><a class="reference internal" href="2.6-compatibility.html">Compatibility Changes in MongoDB 2.6</a><ul>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#index-changes">Index Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#enforce-index-key-length-limit">Enforce Index Key Length Limit</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#index-specifications-validate-field-names">Index Specifications Validate Field Names</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#ensureindex-and-existing-indexes"><code class="docutils literal"><span class="pre">ensureIndex</span></code> and Existing Indexes</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#write-method-acknowledgements">Write Method Acknowledgements</a></li>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#db-collection-aggregate-change"><code class="docutils literal"><span class="pre">db.collection.aggregate()</span></code> Change</a></li>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#write-concern-validation">Write Concern Validation</a></li>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#security-changes">Security Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#new-authorization-model">New Authorization Model</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#ssl-certificate-hostname-validation">SSL Certificate Hostname Validation</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#dsphere-index-version-2"><code class="docutils literal"><span class="pre">2dsphere</span></code> Index Version 2</a></li>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#log-messages">Log Messages</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#timestamp-format-change">Timestamp Format Change</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#package-configuration-changes">Package Configuration Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#default-bindip-for-rpm-deb-packages">Default <code class="docutils literal"><span class="pre">bindIp</span></code> for RPM/DEB Packages</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#snmp-changes">SNMP Changes</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#remove-method-signature-change">Remove Method Signature Change</a></li>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#update-operator-syntax-validation">Update Operator Syntax Validation</a></li>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#updates-enforce-field-name-restrictions">Updates Enforce Field Name Restrictions</a></li>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#query-and-sort-changes">Query and Sort Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#enforce-field-name-restrictions">Enforce Field Name Restrictions</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#sparse-index-and-incomplete-results">Sparse Index and Incomplete Results</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#sort-specification-values"><code class="docutils literal"><span class="pre">sort()</span></code> Specification Values</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#skip-and-id-queries"><code class="docutils literal"><span class="pre">skip()</span></code> and <code class="docutils literal"><span class="pre">_id</span></code> Queries</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#explain-retains-query-plan-cache"><code class="docutils literal"><span class="pre">explain()</span></code> Retains Query Plan Cache</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#geospatial-changes">Geospatial Changes</a><ul>
<li class="toctree-l4"><a class="reference internal" href="2.6-compatibility.html#maxdistance-changes"><code class="docutils literal"><span class="pre">$maxDistance</span></code> Changes</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-compatibility.html#deprecated-uniquedocs">Deprecated <code class="docutils literal"><span class="pre">$uniqueDocs</span></code></a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-compatibility.html#stronger-validation-of-geospatial-queries">Stronger Validation of Geospatial Queries</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#query-operator-changes">Query Operator Changes</a><ul>
<li class="toctree-l4"><a class="reference internal" href="2.6-compatibility.html#not-query-behavior-changes"><code class="docutils literal"><span class="pre">$not</span></code> Query Behavior Changes</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-compatibility.html#null-comparison-queries"><code class="docutils literal"><span class="pre">null</span></code> Comparison Queries</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-compatibility.html#all-operator-behavior-change"><code class="docutils literal"><span class="pre">$all</span></code> Operator Behavior Change</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-compatibility.html#mod-operator-enforces-strict-syntax"><code class="docutils literal"><span class="pre">$mod</span></code> Operator Enforces Strict Syntax</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-compatibility.html#where-must-be-top-level"><code class="docutils literal"><span class="pre">$where</span></code> Must Be Top-Level</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-compatibility.html#exists-and-notablescan"><code class="docutils literal"><span class="pre">$exists</span></code> and <code class="docutils literal"><span class="pre">notablescan</span></code></a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-compatibility.html#minkey-and-maxkey-queries"><code class="docutils literal"><span class="pre">MinKey</span></code> and <code class="docutils literal"><span class="pre">MaxKey</span></code> Queries</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-compatibility.html#nested-array-queries-with-elemmatch">Nested Array Queries with $elemMatch</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#text-search-compatibility">Text Search Compatibility</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#replica-set-sharded-cluster-validation">Replica Set/Sharded Cluster Validation</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#shard-name-checks-on-metadata-refresh">Shard Name Checks on Metadata Refresh</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html#replica-set-vote-configuration-validation">Replica Set Vote Configuration Validation</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#time-format-changes">Time Format Changes</a></li>
<li class="toctree-l2"><a class="reference internal" href="2.6-compatibility.html#other-resources">Other Resources</a></li>
</ul>
</li>
</ul>
</div>
<p>Some changes in 2.6 can affect <a class="reference internal" href="2.6-compatibility.html"><span class="doc">compatibility</span></a> and may require user actions. The
2.6 <a class="reference internal" href="../reference/program/mongo.html#bin.mongo" title="bin.mongo"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongo</span></code></a> shell provides a
<a class="reference external" href="https://docs.mongodb.com/v2.6/reference/method/db.upgradeCheckAllDBs">db.upgradeCheckAllDBs()</a> method to perform a check for upgrade
preparedness for some of these changes.</p>
<p>See <a class="reference internal" href="2.6-compatibility.html"><span class="doc">Compatibility Changes in MongoDB 2.6</span></a> for a detailed list of
compatibility changes.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20%3D%20SERVER%20AND%20fixVersion%20in%20(%222.5.0%22%2C%20%222.5.1%22%2C%20%222.5.2%22%2C%20%222.5.3%22%2C%20%222.5.4%22%2C%20%222.5.5%22%2C%20%222.6.0-rc1%22%2C%20%222.6.0-rc2%22%2C%20%222.6.0-rc3%22)%20AND%20%22Backwards%20Compatibility%22%20in%20(%20%22Minor%20Change%22%2C%22Major%20Change%22%20)%20ORDER%20BY%20votes%20DESC%2C%20issuetype%20DESC%2C%20key%20DESC">All Backwards incompatible changes (JIRA)</a>.</p>
</div>
</div>
<div class="section" id="upgrade-process">
<h3>Upgrade Process<a class="headerlink" href="#upgrade-process" title="Permalink to this headline">¶</a></h3>
<div class="toctree-wrapper hidden compound">
<ul>
<li class="toctree-l1"><a class="reference internal" href="2.6-upgrade.html">Upgrade MongoDB to 2.6</a><ul>
<li class="toctree-l2"><a class="reference internal" href="2.6-upgrade.html#upgrade-recommendations-and-checklists">Upgrade Recommendations and Checklists</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade.html#upgrade-requirements">Upgrade Requirements</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade.html#preparedness">Preparedness</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade.html#authentication">Authentication</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade.html#downgrade-limitations">Downgrade Limitations</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade.html#package-upgrades">Package Upgrades</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-upgrade.html#upgrade-mongodb-processes">Upgrade MongoDB Processes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade.html#upgrade-standalone-mongod-instance-to-mongodb-2-6">Upgrade Standalone <code class="docutils literal"><span class="pre">mongod</span></code> Instance to MongoDB 2.6</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade.html#upgrade-a-replica-set-to-2-6">Upgrade a Replica Set to 2.6</a><ul>
<li class="toctree-l4"><a class="reference internal" href="2.6-upgrade.html#upgrade-secondary-members-of-the-replica-set">Upgrade secondary members of the replica set.</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-upgrade.html#step-down-the-replica-set-primary">Step down the replica set primary.</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-upgrade.html#upgrade-the-primary">Upgrade the primary.</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade.html#upgrade-a-sharded-cluster-to-2-6">Upgrade a Sharded Cluster to 2.6</a><ul>
<li class="toctree-l4"><a class="reference internal" href="2.6-upgrade.html#considerations">Considerations</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-upgrade.html#upgrade-sharded-clusters">Upgrade Sharded Clusters</a><ul>
<li class="toctree-l5"><a class="reference internal" href="2.6-upgrade.html#disable-the-balancer">Disable the Balancer.</a></li>
<li class="toctree-l5"><a class="reference internal" href="2.6-upgrade.html#upgrade-the-cluster-s-meta-data">Upgrade the cluster’s meta data.</a></li>
<li class="toctree-l5"><a class="reference internal" href="2.6-upgrade.html#ensure-mongos-upgrade-process-completes-successfully">Ensure <code class="docutils literal"><span class="pre">mongos</span> <span class="pre">--upgrade</span></code> process completes successfully.</a></li>
<li class="toctree-l5"><a class="reference internal" href="2.6-upgrade.html#upgrade-the-remaining-mongos-instances-to-v2-6">Upgrade the remaining <code class="docutils literal"><span class="pre">mongos</span></code> instances to v2.6.</a></li>
</ul>
</li>
<li class="toctree-l4"><a class="reference internal" href="2.6-upgrade.html#complete-sharded-cluster-upgrade">Complete Sharded Cluster Upgrade</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-upgrade.html#action-procedure">Upgrade Procedure</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade.html#stop-the-existing-mongod-instance">Stop the existing <code class="docutils literal"><span class="pre">mongod</span></code> instance.</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade.html#start-the-new-mongod-instance">Start the new <code class="docutils literal"><span class="pre">mongod</span></code> instance.</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="2.6-upgrade-authorization.html">Upgrade User Authorization Data to 2.6 Format</a><ul>
<li class="toctree-l2"><a class="reference internal" href="2.6-upgrade-authorization.html#considerations">Considerations</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade-authorization.html#complete-all-other-upgrade-requirements">Complete all other Upgrade Requirements</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade-authorization.html#timing">Timing</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade-authorization.html#replica-sets">Replica Sets</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade-authorization.html#sharded-clusters">Sharded Clusters</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-upgrade-authorization.html#requirements">Requirements</a></li>
<li class="toctree-l2"><a class="reference internal" href="2.6-upgrade-authorization.html#procedure">Procedure</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade-authorization.html#connect-to-mongodb-instance">Connect to MongoDB instance.</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-upgrade-authorization.html#upgrade-authorization-schema">Upgrade authorization schema.</a><ul>
<li class="toctree-l4"><a class="reference internal" href="2.6-upgrade-authorization.html#run-authschemaupgrade-command">Run <code class="docutils literal"><span class="pre">authSchemaUpgrade</span></code> command.</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-upgrade-authorization.html#sharded-cluster-authschemaupgrade-consideration">Sharded cluster <code class="docutils literal"><span class="pre">authSchemaUpgrade</span></code> consideration.</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-upgrade-authorization.html#result">Result</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="2.6-downgrade.html">Downgrade MongoDB from 2.6</a><ul>
<li class="toctree-l2"><a class="reference internal" href="2.6-downgrade.html#downgrade-recommendations-and-checklist">Downgrade Recommendations and Checklist</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html#downgrade-path">Downgrade Path</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html#preparedness">Preparedness</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html#procedures">Procedures</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="2.6-downgrade.html#downgrade-2-6-user-authorization-model">Downgrade 2.6 User Authorization Model</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html#considerations">Considerations</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html#access-control-prerequisites">Access Control Prerequisites</a><ul>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#connect-as-user-with-privileges-to-manage-users-and-roles">Connect as user with privileges to manage users and roles.</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#create-a-role-with-required-privileges">Create a role with required privileges.</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#create-a-user-with-the-new-role">Create a user with the new role.</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#authenticate-as-the-new-user">Authenticate as the new user.</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html#procedure">Procedure</a><ul>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#connect-and-authenticate-to-mongodb-instance">Connect and authenticate to MongoDB instance.</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#create-backup-of-2-6-admin-system-users-collection">Create backup of 2.6 <code class="docutils literal"><span class="pre">admin.system.users</span></code> collection.</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#update-the-version-document-for-the-authschema">Update the version document for the <code class="docutils literal"><span class="pre">authSchema</span></code>.</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#remove-existing-documents-from-the-admin-system-users-collection">Remove existing documents from the <code class="docutils literal"><span class="pre">admin.system.users</span></code> collection.</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#copy-documents-from-the-admin-system-backup-users-collection">Copy documents from the <code class="docutils literal"><span class="pre">admin.system.backup_users</span></code> collection.</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#id1">Update the version document for the <code class="docutils literal"><span class="pre">authSchema</span></code>.</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html#result">Result</a></li>
</ul>
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<li class="toctree-l2"><a class="reference internal" href="2.6-downgrade.html#downgrade-updated-indexes">Downgrade Updated Indexes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html#text-index-version-check">Text Index Version Check</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html#dsphere-index-version-check"><code class="docutils literal"><span class="pre">2dsphere</span></code> Index Version Check</a></li>
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<li class="toctree-l2"><a class="reference internal" href="2.6-downgrade.html#downgrade-mongodb-processes">Downgrade MongoDB Processes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html#downgrade-2-6-standalone-mongod-instance">Downgrade 2.6 Standalone <code class="docutils literal"><span class="pre">mongod</span></code> Instance</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html#downgrade-a-2-6-replica-set">Downgrade a 2.6 Replica Set</a><ul>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#downgrade-each-secondary-member-one-at-a-time">Downgrade each secondary member, one at a time.</a><ul>
<li class="toctree-l5"><a class="reference internal" href="2.6-downgrade.html#replace-and-restart-secondary-mongod-instances">Replace and restart secondary <code class="docutils literal"><span class="pre">mongod</span></code> instances.</a></li>
<li class="toctree-l5"><a class="reference internal" href="2.6-downgrade.html#allow-secondary-to-recover">Allow secondary to recover.</a></li>
</ul>
</li>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#step-down-the-primary">Step down the primary.</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#replace-and-restart-former-primary-mongod">Replace and restart former primary <code class="docutils literal"><span class="pre">mongod</span></code>.</a></li>
</ul>
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<li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html#downgrade-a-2-6-sharded-cluster">Downgrade a 2.6 Sharded Cluster</a><ul>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#requirements">Requirements</a></li>
<li class="toctree-l4"><a class="reference internal" href="2.6-downgrade.html#id4">Procedure</a></li>
</ul>
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</ul>
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<li class="toctree-l2"><a class="reference internal" href="2.6-downgrade.html#action-procedure">Downgrade Procedure</a><ul>
<li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html#stop-the-existing-mongod-instance">Stop the existing <code class="docutils literal"><span class="pre">mongod</span></code> instance.</a></li>
<li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html#start-the-new-mongod-instance">Start the new <code class="docutils literal"><span class="pre">mongod</span></code> instance.</a></li>
</ul>
</li>
</ul>
</li>
</ul>
</div>
<p>See <a class="reference internal" href="2.6-upgrade.html"><span class="doc">Upgrade MongoDB to 2.6</span></a> for full upgrade instructions.</p>
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<div class="section" id="download">
<h3>Download<a class="headerlink" href="#download" title="Permalink to this headline">¶</a></h3>
<p>To download MongoDB 2.6, go to the <a class="reference external" href="http://www.mongodb.org/downloads">downloads page</a>.</p>
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<div class="section" id="other-resources">
<h3>Other Resources<a class="headerlink" href="#other-resources" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/secure/IssueNavigator.jspa?reset=true&amp;jqlQuery=project+%3D+SERVER+AND+fixVersion+in+%28%222.5.0%22%2C+%222.5.1%22%2C+%222.5.2%22%2C+%222.5.3%22%2C+%222.5.4%22%2C+%222.5.5%22%2C+%222.6.0-rc1%22%2C+%222.6.0-rc2%22%2C+%222.6.0-rc3%22%29">All JIRA issues resolved in 2.6</a>.</li>
<li><a class="reference external" href="https://github.com/mongodb/mongo/blob/v2.6/distsrc/THIRD-PARTY-NOTICES">All Third Party License Notices</a>.</li>
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